John McCain heads to California Wednesday with a fresh sense of purpose and a possible endorsement from Rudy Giuliani, after a win in Florida's Republican primary that bested archrival Mitt Romney and left Giuliani few options but to drop his own presidential bid.

Hillary Clinton also handily won the largely ceremonial Democratic contest in the state.

Click here to read more about Clinton's victory in the Democratic primary in Florida.

The primary was the last major opportunity for candidates to pick up momentum going into Super Tuesday, Feb. 5, when 24 states hold primaries and caucuses for both parties.

With 100 percent of precincts reporting, McCain had 36 percent and Romney 31 percent, followed by Rudy Giuliani with 15 percent, Mike Huckabee with 13 percent and Ron Paul with 3 percent.

Among the Democrats, Clinton had 50 percent in Florida, followed by Barack Obama at 33 percent and John Edwards at 15 percent, with 100 percent of precincts reporting.

The winner-take-all Florida race hands McCain the state's 57 delegates to the GOP nominating convention. That's half the delegates the state would have normally sent to this year's convention but the Republican National Committee penalized the state for holding its primary ahead of Super Tuesday.

For Republicans, the race marked the fiercest battle to date between McCain and Romney, who went after each other on issues ranging from the Iraq war to conservative credentials to taxes.

Click here for a photo essay of Florida's Primary Election Day.

In his victory speech, McCain drove home several of the points that he tried to make to voters -- promoting a strong national security, limited federal spending, a continuation of Ronald Reagan's conservative legacy and his ability to defeat whoever is the Democratic nominee.

"Government must defend our nation's security wisely and effectively because the cost of our defense is so dear to us, measured in losses so hard to bear in the heartbreak of so many families," he said. "Government must respect our values because they are the true source of our strength and enforce the rule of law which distinguishes successful democracies from failed societies and is the first offense of freedom."

Building on the confidence of a candidate with newfound energy, McCain said he is pumped up ahead of the enormous Feb. 5 contest.

"I intend to win it and be the nominee of our party," he told supporters in Miami.

But he also congratulated Romney's supporters for putting up a tough fight.

"You fought hard for your candidate and the margin that separated us tonight surely isn't big enough for me to brag about or you to despair," he said.

McCain still has to defeat Romney, Huckabee and Paul to win the GOP nomination, but in anticipation of the Giuliani endorsement now expected on Wednesday, he called the former New York City mayor "an exceptional American leader" who is "an inspiration to me and millions of Americans."

For Giuliani, a Florida win was considered critical. The former front-runner had bypassed all the other early voting states in favor of pursuing victory in Florida ahead of Feb. 5, but with each primary loss his poll numbers dropped.

Speaking to supporters Tuesday night, Giuliani sounded like a candidate who was ready to throw in the towel despite telling reporters that he is moving on to California. Aides told FOX News that a departure was imminent.

"I believe that our party will be stronger as a result of the competition that we're going through, but win or lose our work is not done because leaders dream of a better future and then they help to bring it into a reality," he said at a campaign party.

"The responsibility of leadership does not end with a single campaign. If you believe in a cause it goes on and you continue to fight for it, and we will," he said.

Elsewhere, a disappointed Romney called McCain to offer his congratulations and told his supporters to hang on for an ongoing fight.

"You guys are my heroes. You took this campaign from nowhere to the very top tier. You worked your hearts out, and you made me a contender. And for that, Ann and I and our family will be forever grateful. Thank you so very much," the former Massachusetts governor said with his wife by his side.

"I'm sure that you are excited here this evening, but a little disappointed, as well," he said before launching into a speech that continued his anti-Washington theme and touted his economic credentials

"Hard-working, innovative, risk-taking, family-oriented, God- fearing, freedom-loving American people have always been the source of America's greatness, and they always will be. And so the right course for America isn't to strengthen our government, but to strengthen our people. And to do that, we're going to have to change Washington, and change will begin with us," Romney said.

As for Huckabee, who hasn't secured a win since the Iowa caucuses Jan. 3, he said he was just pleased for a strong showing in Florida.

“For those of you who think I would be discouraged … we’re gonna play all nine innings of this ball game,” he told supporters Tuesday night in St. Louis, where he was watching the Florida returns. “Even the Cardinals occasionally have a rough inning, but they know how to win championships.”

The former Arkansas governor later told FOX News he's nowhere near quitting.

"You know, when we look at the states that are in play next week -- and we're leading in most of those southern states, Missouri, Oklahoma, Arkansas, Tennessee, Alabama and Georgia -- these are states where we really believe we're going to do well. And we think we'll pick up some delegates in some of the other states, possibly Montana and Minnesota. So we're a long way -- you know, this is one inning, and we're going to be in this thing," he said.

In the roughest battle so far in this short Republican primary season, McCain picked up key endorsements from Florida Sen. Mel Martinez and Gov. Charlie Crist, both of whom traveled with the candidate in the last few days and stood behind him as he spoke Tuesday night.

FOX News exit polls seemed to indicate that the endorsements did matter to voters. McCain led among seniors, Hispanics, Catholics and those who said Crist's endorsement was important. Romney led among evangelicals and individuals who put illegal immigration at the top of their list of most important issues.

Exit polling showed that McCain won large margins in Miami-Dade County, where Cuban Americans helped give him a 37,000 vote margin, taking the county 48-14 percent over Romney. McCain was also helped by big margins in the Tampa Bay area, where military and retired voters came out in force. That area is also the home base of Crist, who gave his surprise endorsement to McCain at a Pinellas County dinner on Saturday night.

Romney carried Orlando and northern portions of Florida as well as affluent counties like Naples, but the margins weren't large enough to overcome McCain's wider win in Miami-Dade. Huckabee, who came in fourth, also carried some southern and southern-accented counties in northern Florida.

While the Democrats were not courted by the candidates as a result of their being prohibited by the Democratic National Committee, the Illinois senator fared well among late-deciding voters, the exit polls showed.

Still, Democrats were also penalized for holding an early contest and will suffer far worse than Republicans. None of the state's delegates will be seated at the Democratic convention in August, a point emphasized by the Obama campaign.

"Now that Senator Clinton has lost badly in South Carolina, she’s trying to assign meaning to a contest that awards zero delegates and where no campaigning has occurred," said campaign spokesman Bill Burton. "Senator Clinton's own campaign has repeatedly said that this is a 'contest for delegates,' and tonight, Florida awarded zero."

Clinton, who held a rally in Florida after polls closed, said Tuesday night that she would fight to get the state's delegates restored.

“I am convinced with this resounding vote, with the millions of Americans who will vote next Tuesday, we will send a clear message that America is back and we’re gonna take charge of our destiny again,” she said.

Florida's vote offered a record turnout for a primary with more than 1.8 million Republicans and 1.6 million Democrats casting their selections. More than a million of those votes were cast by absentee ballots.