All the hand-shaking, diner-visiting, coffee-drinking, stump-speaking, driveway-shoveling, teeth-chattering, door-knocking, leaflet-passing, face-to-face campaigning that the 2008 presidential candidates have lost sleep over in Iowa culminates Thursday with the state's first-in-the-nation caucuses.

Candidates are scrambling to make their closing arguments in the last 24 hours, together packing in dozens of appearances in Iowa and blanketing the airwaves with advertisements.

Watch for special FOX News Channel's live coverage of the Iowa caucuses starting at 2 p.m. EST, and make sure to tune in for the caucus returns starting at 8:30 p.m.

On the Democratic side, the race has boiled down to a three-way dead heat between Hillary Clinton, John Edwards and Barack Obama, with each candidate scrambling to be seen as the one who has the chops and the moxie to bring true change to Washington. RealClearPolitics.com poll averages from Thursday show Obama with 30.8 percent, Clinton with 29.2 percent and Edwards with 26 percent. 

Delaware Sen. Joe Biden and New Mexico Gov. Bill Richardson, with 5.4 and 5.2 percent in those polls, respectively, could still shake up that race with last-minute surges in support. Ohio Rep. Dennis Kucinich and Connecticut Sen. Chris Dodd are also vying for support in the race.

On the Republican side, the race has broken into a war of ads and a war of words among top-shelf candidates. But the race here has divided into three distinct tiers, even though Iowa doesn't reflect GOP standings elsewhere -- not yet anyway. RealClearPolitics poll averages show Mike Huckabee with 29.7 percent and Mitt Romney with 26.7 percent at the top. The averages show John McCain with 11.8 percent and Fred Thompson with 11.7 percent in the middle. Finally, they show Ron Paul with 7.3 percent and Rudy Giuliani with 6 percent.

For all the hype, the product of the Iowa caucuses is determined by the choices of relatively few residents, who are courted heavily. This year, between 120,000 and 150,000 people are expected to vote in the Democratic caucuses, while between 80,000 and 90,000 are expected to vote in the Republican caucuses.

Here's a rundown of the final gambits in Iowa from the presidential field:

DEMOCRATIC RACE

Hillary Clinton

-- On the air: With a massive ad buy in media markets across the state Wednesday night, Clinton has a two-minute, state-of-the-union-type spot where she makes the final case for her candidacy.

Ticking off the "faltering economy," "47 million people without health care," and the war in Iraq, the New York senator declares "America is at a crossroads." In the ad she is gentle and soft-spoken, but firmly asserts she is the candidate voters need to start a "new beginning" after seven years of the Bush administration. She attempts to tie together the themes of change and experience.

"I'll work my heart out to bring the country we love the new beginning it needs, and I will be ready to start on day one," she says.

Click here to see the Clinton ad.

Clinton also made a cameo appearance with David Letterman as the "Late Show" host returned to work for the first time since writers went on strike two months ago.

-- On the stump: In every speech for the past two weeks, Clinton has worked in a wrap-up of her resume, saying she's got the experience that matters: "The best way for you to know what kind of changes I will make is to look at what I've done."

-- Final strategy: Like everyone in the race, Clinton is relying on getting her supporters to the polls. The campaign also shipped out 621 snow shovels to volunteers across the state. The campaign is still door-knocking, and plans to rent SUVs to drive Iowans to caucus Thursday. The campaign claims its had 4,900 requests for rides.

Her final message to Iowa Democrats is don't blow this one.

"Tomorrow night, not just the eyes of America but the eyes of the world will be on you," she said Wednesday. "It is perhaps the most important political decision you will ever make."

Barack Obama

-- On the air: Obama, too, purchased a two-minute ad across Iowa. 

"This country's ready for a leader who will bring us together: that's the only way we're gonna win this election and that's actually how we'll actually fix health care and make college affordable, become energy independent and end this war," he says in the ad. "So I ask you to caucus tomorrow, not just for me, but for your hopes; for your dreams; for the America you believe is possible."

Click here to see the Obama ad.

And in an e-mail to Iowa supporters Tuesday, Obama state director Paul Tewes cast the Illinois senator as the Democratic candidate who can attract independents and Republicans.

-- On the stump: The Illinois senator has from the beginning been campaigning as the candidate of change, even though Edwards and Clinton have tried to take that mantle from him.

At a kickoff rally in Davenport, Iowa, Obama said the stakes are too high for voters to "do the same old things with the same old folks."

"My intention is to be so persuasive, so dazzling this morning, that if there's anybody in this auditorium who's still ... undecided on who to caucus for, that a light bulb will go off, a beam of light will shine down on you," he said. "You will have an epiphany and you suddenly say, ‘I understand now I have to caucus for Obama.'"

There was a slight glitch for Obama Wednesday. He stood on a small, plywood platform at the rally, explaining that the campaign truck was unable to deliver the normal platform because the truck carrying the equipment hit a deer.

"We feel bad for the deer. And we feel bad for the truck," Obama joked.

-- Final strategy: Obama, in particular, has bet his campaign on the support of young voters, first-time caucus-goers, independents and Democrats attracted to his message of change. A victory in Iowa would validate the strategy, and presumably give him a boost in New Hampshire, where independents can vote in either primary.

John Edwards

-- On the stump: Edwards, who has pitched himself as the populist class warrior with the guts to make the changes that other candidates only talk about, launched a 36-hour "Marathon for the Middle Class" tour going into the caucuses.

The former North Carolina senator intended to hit 15 Iowa counties, and discussed one specific policy initiative in each of the 36 hours. He culminated the effort in Des Moines with a rally featuring musician John Mellencamp.

He's hitting hard his themes of "corporate greed" working to the detriment of the American people. He started campaigning before dawn Wednesday, and, like his rivals, plans to supplement his in-person visits with an ad on Iowa television.

-- On the air: The one-minute TV spot features laid-off Maytag worker Doug Bishop, praising Edwards for pledging to his son four years ago that "I'm going to keep fighting for your daddy's job."

-- Final strategy: Health care has become a lead domestic issue among the Democratic candidates, and it surfaced once again Wednesday with Edwards, who said there are "substantive differences" between his plan and Obama's.

But then his wife Elizabeth interrupted to do the talking:

"I heard a radio commercial for Senator Obama, where it said in there that his health care program covered more Americans than either Senator Clinton's or John's. That is actually not true," she said. "There's 15 million or so ... people like myself and some recent college graduates... who are left out of his plan. And it's just complete untruth."

Hoping to wrest the mantle of "change" from Obama, Edwards must tap into anger at Washington. He also is casting himself, backed by a recent poll, as the only Democrat who could beat any Republican candidate.

Joe Biden

-- On the stump: Though he's polling in the low single digits, Biden's campaign is still pulling for a third- or fourth-place finish in Iowa, and scheduled a full day of Iowa events Wednesday.

The veteran Delaware senator is attracting some last-minute interest, drawing more than 500 to an event in Des Moines Tuesday.

We're drawing first-tier crowds," Biden's son Delaware Attorney General Beau Biden told FOX News Wednesday. "Something's happening here on the ground in Iowa. And I think we're going to surprise people tomorrow night." 

-- Final strategy: As chairman of the Senate Foreign Relations Committee, Biden has tried highlight his foreign policy experience, at a time when the issue has taken center stage with the assassination of former Pakistani Prime Minister Benazir Bhutto.

Bill Richardson

-- On the stump: Richardson, too, is polling in the low single digits but scheduled a full day of events in Iowa leading up to the caucuses.

-- Final strategy: The New Mexico governor has touted his experience -- as a congressman, an ambassador to the United Nations and secretary of the Department of Energy -- throughout the race and recently garnered attention for making bold statements on foreign policy.

After Bhutto was assassinated, Richardson called not only for an independent investigation, but for Pakistani President Pervez Musharraf to step down.

Richardson has also tried to distance from those in Washington.

"The Washington insiders have it tragically wrong," he said in his statement on Musharraf.

Dennis Kucinich

The Ohio congressman has spent his days on the campaign trail hammering his Democratic opponents who voted for the war in Iraq -- but faced with weak poll numbers, Kucinich urged voters on Tuesday to support anti-war Barack Obama as their second choice.

Kucinich told FOX News Wednesday he still hopes caucus-goers choose him first, but that if he doesn't win the 15 percent needed to qualify for delegates to go to the next step, Iowans should go for Obama.

"Sen. Obama and I have one thing in common: change," Kucinich said in a statement.

Christopher Dodd, Mike Gravel

Connecticut Sen. Chris Dodd and former Alaska Sen. Mike Gravel have also had a tough time registering in the polls.

But Dodd still slated day of celebrations and visits in Iowa Thursday. And perhaps thinking optimistically, he's got a tool on his Web site helping Iowa residents figure out where they need to go to caucus.

Meanwhile, Gravel plans to be in New Hampshire campaigning in an RV through Jan. 8, when that state holds its primary.

REPUBLICAN RACE

Mitt Romney

-- On the stump: Romney has gone into the final stretch stressing that this is a "serious election," a somber time with no place for "frivolity" -- a likely jab at rival Mike Huckabee, who has become known for his quick-witted, and sometimes glib, remarks at debates and campaign events.

With Huckabee posing a stiff challenge to Romney, he has sought to exude confidence even while playing down expectations for the caucuses.

"I honestly believe that I'm going to get the nomination for our party, and I can't tell you exactly which states will come my way ... but ultimately I think I'll be the nominee," he said in Bettendorf, Iowa, Wednesday.

-- On the air: The former Massachusetts governor talked about keeping taxes down and fighting illegal immigration Wednesday in Iowa. But he's had to go negative over the airwaves in recent days, fending off Huckabee in Iowa and McCain in New Hampshire. He's challenged McCain for voting against President Bush's tax cuts and for being too lenient on illegal immigration -- charges that have brought criticism even from Huckabee.

"Sen. McCain is an honorable person. He's been in the Senate for 25 years or more," Romney clarified Wednesday. "But I've actually been leading during that time."

-- Final strategy: Romney hauled in big-name backer, former House Speaker Dennis Hastert, to introduce him at an event in an airline hangar. Hastert endorsed Romney in January 2007. In his introduction, Hastert said the former Massachusetts governor is the candidate who can wrangle disparate sides. 

"In a state where Ted Kennedy isn't liberal enough for some voters, Mitt Romney defended the values that helped make America great: marriage, family, and community. That is the Romney way. "

Perhaps a sign of the tight race against Huckabee, Romney fended off allegations that he is hitting below the belt, denying allegations that Romney supporters have been calling Huckabee backers and giving them wrong caucus locations.

"It is not us," the Romney campaign said in a statement.

Mike Huckabee

-- On the air: Though polls show Huckabee's Iowa surge peaking in early December, the former Arkansas governor has fought to hold on to his razor-thin advantage over Romney. Huckabee appeared on "The Tonight Show with Jay Leno" Wednesday after spending the day talking like an underdog. Huckabee faced some flak for crossing the striking writers' picket line to go on the air. He also rejected claims that he was abandoning Iowa for Los Angeles.

-- On the stump: The Southern Baptist pastor spoke before a fully-packed pizza parlor and an overflow room on Wednesday to highlight the importance of "the sanctity of life." Though touting Christian values in ads and on the stump, Huckabee's been hit hard by Romney for pushing tax increases while governor and granting pardons and commutations. He answered with the toughest rhetoric yet of the campaign over the weekend, suggesting Romney is "desperate and dishonest."

Huckabee then filmed an ad repeating those charges against Romney portraying him soft as soft on gun control and abortion. But in an unusual sequence, Huckabee called a news conference to announce he was pulling the ad. If that was a truce, it hardly worked, because FOX News obtained a copy after the campaign unsuccessfully attempted to screen it with reporters, and the ad got out anyway.

But Huckabee was back at Romney Wednesday, saying "how many people in America could relate to a person who could write checks of tens of millions of dollars to run for an office and not miss it at all?"

-- Final strategy: Huckabee's suffered some slip-ups on the campaign trail, recently making a series of gaffes exposing gaps in his knowledge on foreign affairs. But he's projected a seemingly unshakable man-of-the-people image that still resonates. In the last two days, the casual candidate has played bass guitar no less than three times at campaign events.

"I'm looking forward to being with ya' for a victory tomorrow night," Huckabee said Wednesday.

"Tomorrow night, let's prove the pundits wrong and the people right. ... You tell your grandkids some day, I was there on that night when we turned American politics on its ear ... when we decided to stand on issues that mattered to us," he said in Mason City, Iowa.

John McCain

-- On the stump: McCain's poll numbers are much better in New Hampshire than Iowa, but he split his time Wednesday between the two states. He kicked off the Iowa stops in the late afternoon with a rally in Dubuque.

The Arizona senator has tried to highlight his foreign policy experience, particularly in the wake of Bhutto's assassination. And though he pledged over the weekend to stop the bitter back-and-forth attacks between him and Romney, he hasn't exactly lived up to the promise.

Instead, he got former presidential candidate and Kansas Republican Sen. Sam Brownback to take his place.

"Mitt Romney has said for months that he is a good manager, and while we were all pleased to see the success of the 2002 Winter Olympics, our country needs a leader. Events like the assassination of Benazir Bhutto stand as stark reminders that the world is a dangerous place, presenting grave challenges to our nation and demanding experienced, courageous leadership," Brownback said in a statement.

McCain also highlighted a statement from U.S. Sen. Lindsey Graham, who said: "I believe foreign policy experience matters. For Governor Romney to say otherwise is naïve ... John McCain has been involved in every significant national security issue of the last 20 years."

Earlier in Derry, N.H., McCain had lunch with supporter Sen. Joe Lieberman. There he attributed his surge to telling the truth, and criticized Romney for changing positions.

Asked how Romney's performance in Iowa would affect him, the 71-year-old senator said: "I'm not fearful of anything - too old to be fearful ... I mean too young to be fearful!"

-- On the air: On Wednesday he launched a new Web ad criticizing his rival. The ad quotes Romney saying, "If we want somebody who has a lot of experience in foreign policy we can simply go to the State Department."

"Is he serious?" the narrator asks.

Click here to see McCain's ads criticizing Romney.

-- Final strategy: McCain has said he has no closing argument per se, but that the take-home point is he's the one with the experience and judgment to lead. He's doing a 24-hour tour of Iowa, where he hasn't run any TV ads, and then returning to New Hampshire Jan. 3.

Rudy Giuliani

-- Off the beaten path: Though he visited Iowa over the weekend, Giuliani gave the Hawkeye State a pass on Wednesday, instead delivering a foreign policy speech in New Hampshire.  

There he said he would immediately double the number of troops under U.S. command in Afghanistan.

"We need to bring a surge to Afghanistan and make it effective, right now," he said.

-- On the air: The former New York mayor has also got a new national ad stressing his ability to handle the threat of terrorism abroad. The ad, "Ready," contains graphic images of attacks and explosions and Islamic extremists.

Final strategy: Giuliani has repeatedly said he's focusing on Florida and the 19 states that hold GOP primaries Feb. 5, in lieu of putting all his efforts into Iowa. Even though he's polling toward the bottom of the pile in Iowa, he's still leading in most national polls. He plans to stay in New Hampshire Thursday for a morning campaign stop, but then heads back to Florida.

Fred Thompson

-- On the stump: The media-buzz around Thompson's campaign has waned since prior to his announcing his candidacy in September, but the former Tennessee senator and Law & Order actor is pushing ahead in Iowa.

He's in the middle of a bus tour where he's trying to visit 50 cities, and is, as he has been for months, trying to pitch himself as the one true conservative in the race. 

-- On the air: On his Web site, Thompson posted a lengthy address to Iowa caucus-goers, discussing his conservatives principles and dedication to fighting for strong borders, national security and the "right to life." In the background is a sign that says "The clear, conservative choice."

Click here to see Thompson's final message to Iowa caucus-goers.

He recently ran an ad in Iowa stressing his opposition to abortion.

 "I am the strong, consistent conservative in the race with national security credentials," Thompson told FOX News Wednesday. "What you see is what you get, and you can tell what I'll do in the future because you know what I did in the past."

Ron Paul

-- On the stump: The libertarian-leaning, Texas congressman, though trailing in the polls nationally, is taking his first shot at the nomination in Iowa very seriously and has drummed up a broad entourage of enthusiastic supporters.

He set a rally in Des Moines Wednesday night to discuss foreign policy with a group of veterans, and is touting endorsements he's received from veterans.

"Dr. Paul, a veteran himself, has a 30-year record, of standing up for veterans," said campaign spokesman Jesse Benton in a statement. "Congressman Paul advocates a stronger America by emphasizing military readiness, secure borders, and the use of our troops only to defend America's national security -- never for nation-building or peacekeeping under the U.N. flag."

Paul has gained steam pushing his anti-war, limited government message, and has racked up record hauls in fundraising. His campaign reported exceeding its original goal of $12 million for the fourth quarter, pulling in nearly $20 million during that period.

-- Final strategy: Paul continues to march out a large following of young, mostly male supporters who are canvassing hard. His campaign has also taken advantage of that following's youth with its skill in inundating the modern media -- Internet blogs -- to get out his message.

Duncan Hunter

California Congressman Duncan Hunter has not quite attracted the same dark horse enthusiasm as Paul. He's barely registering in the polls, but has forged his campaign -- like former candidate Tom Tancredo -- on outrage over what he considers inaction regarding illegal immigration and border security.

Alan Keyes 

Former Amb. and 2004 Obama Senate opponent Alan Keyes has also had a tough time since announcing his candidacy in September. But he did participate in a recent debate in Des Moines, and planned rallies in Iowa on Wednesday and Thursday. 

FOX News' Carl Cameron, Major Garrett, Aaron Bruns, Mosheh Oinounou, Shushannah Walshe, Malini Bawa, Cristina Corbin, Serafin Gomez and Bonney Kapp and The Associated Press contributed to this report.