Befitting the status of a twice-victorious primary race leader, John Kerry (search) took flak from his rivals Monday, as the other Democratic presidential candidates sought to emphasize the front-runner's support from special interests.

The attacks on Kerry by Sen. John Edwards (search) and former Vermont Gov. Howard Dean (search) came just before the first "Super Tuesday" of the 2004 campaign. Seven states are holding primaries or caucuses, and Kerry is the favorite in at least five contests.

For more on the campaign, click to view Foxnews.com's You Decide 2004 page.

Edwards was campaigning Monday in South Carolina, where the North Carolina senator tops the polls. After distinguishing himself as a candidate who would not go negative on his fellow candidates, Edwards drew a clear contrast between himself and Kerry.

Edwards said Kerry accepted contributions from lobbyists and supported trade pacts that Edwards contended have cost U.S. jobs.

"I don't take contributions from lobbyists, and he obviously does," Edwards told reporters.

Kerry trailed Edwards in the latest polls taken in the South Carolina primary, which Edwards has said he must win in his bid for the nomination. Kerry, a Massachusetts senator, led in polls taken in five other states holding delegate elections Tuesday and was virtually tied in another, Oklahoma, with Wesley Clark (search).

Kerry said he was confident he could win in the South.

"We're not going to convince the South or any other part of the country that we Democrats know how to keep America safe unless we can stand up to him — Bush — on national security," the Massachusetts senator said in a satellite interview with South Carolina television stations. "I have a 35-year record of fighting for my country, fighting in a war, fighting against a war. This is not the time for on-the-job training in the White House on national security issues."

Dean, who fell to third and second in Iowa and New Hampshire respectively, on Sunday pounded Kerry for his financial ties to special interests, saying those links cast doubt on Kerry's claim to be the champion of the battle against them.

"He misrepresented himself, grossly misrepresented himself, as a candidate who would take on special interests in Washington," said Dean, once considered the front-runner.

Kerry defended himself.

"My record responds to that," he said. "I have fought powerful special interests every step of the way."

He also blasted Dean for going back on his vow to stay away from negative campaign tactics.

"I don't know what happened to Dean's positive campaign, but it is the shortest-lived positive campaign I have ever seen," Kerry said Monday in Tucson.

The Democratic candidates also took slaps at the $2.4 trillion budget Bush sent to Congress on Monday.

Clark said the budget showed Bush's priorities were "tax cuts for the rich and tough luck for everyone else." Connecticut Sen. Joe Lieberman (search) said the country "can't afford another four years of the same destructive fiscal leadership." Kerry said Bush's budget represented the "same failed Republican prescription that has caused Bush to lose 2.5 million jobs in the last three years."

The Stakes on Tuesday

Arizona, Delaware, Missouri, Oklahoma and South Carolina will hold primaries Tuesday; New Mexico and North Dakota will hold caucuses. More than 21 million people and 269 Democratic delegates will be involved in the first real test of the candidates' national legitimacy.

If Kerry sweeps on Tuesday, it would jeopardize the campaigns of Edwards and Clark, leaving Kerry free to focus on Dean.

If Edwards wins South Carolina and polls strongly enough to win delegates in Missouri and Oklahoma, he can continue as a viable candidate.

If Clark wins Oklahoma Tuesday and comes in a strong second in Arizona, he also can feasibly move on. Dean has already conceded Arizona, Missouri, Oklahoma and South Carolina, but winning some delegates in one or two states could help him in Michigan and Wisconsin later on.

South Carolina: Do or Die for Edwards

Zogby/Reuters/MSNBC polls released Monday showed Kerry building on his leads in Missouri and Arizona, Edwards up by 5 points in South Carolina and Clark hanging on to his lead in Oklahoma.

The polls of 600 likely voters in each state were conducted from Jan. 30-Feb. 1 and had margins of error of 4 percentage points.

The polls also showed large numbers of undecided voters, which could sway the races.

Polling of South Carolina voters by Zogby found that Edwards had 30 percent of the vote, Kerry in second place with 25 percent, Dean and Clark tied for third with 10 percent and all other candidates in single digits.

An American Research Group poll conducted Jan. 29-Jan. 31 gave Edwards the same 30 percent, Kerry 23 percent, Clark 12 percent and all other candidates single digits.

Kerry was "doing extremely well here, he's coming up in the polls in John Edwards' backyard," former Georgia Sen. Max Cleland, a Kerry supporter and also a Vietnam veteran, told Fox News on Monday.

"Not only is he doing well here, he's doing extremely well in closing in on Clark in Oklahoma" and in other states, Cleland added. "I sense that the American people are beginning to consolidate around John Kerry."

When asked by reporters if he can carry on without a South Carolina win, Edwards said, "I'm running a national campaign. If I win here on Tuesday, as a practical matter, we're probably down to a two-person race."

But he may have to watch his back.

"So far, Kerry's close has been very significant," said Democratic pollster Carey Crantford in South Carolina, noting that while Kerry's support there was in the teens last week, he's now only 5 points behind Edwards.

"It's going to go down to the wire. So far, Edwards has been able to maintain a significant lead and we'll see how it ends up tomorrow," Crantford continued. "Edwards' message really hits home here in South Carolina," but Kerry has "significant electability."

The South Carolina Democratic Party was seeking to have voters sign an oath saying they're registered voters of that precinct and consider themselves Democrats. Although the Palmetto State's primaries are technically open, some political observers say independents may not feel comfortable signing the oath and many may not come out and vote.

The party later on Monday axed the oath, saying it "didn't want people to not feel welcome to vote."

In Arizona, the Zogby poll found that Kerry has the lead in the Grand Canyon State with 40 percent of the vote. Clark got 27 percent, Dean 13 percent and Lieberman and Edwards got 6 percent. Ohio Rep. Dennis Kucinich (search) received only 1 percent.

A Missouri poll found that Kerry has a whopping 50 percent of the vote, while Clark is in a statistical dead heat with Kerry in Oklahoma.

Leaders of the national Democratic Party have suggested candidates who don't win one or two races this week drop out of the running altogether.

The Race for National Support

Kerry on Monday won the backing of the United Farm Workers Union, The National Treasury Employees Union, The Sheet Metal Workers International Association, Washington Gov. Gary Locke and New York Attorney General Eliot Spitzer.

"With his long record of standing up for all Americans against special interests, John Kerry is the best candidate for president," Spitzer said in a statement.

In South Carolina, Edwards continued to dismiss suggestions he could join Kerry as a running mate.

"I think you should ask Senator Kerry whether he's interested in being vice president," said Edwards, his voice growing hoarse.

As virtually all the candidates run low on cash, campaigns are deciding which states to focus their hardest efforts on.

"I don't think any campaign is flush right now, and we certainly have to rationalize our resources ... and choose some targets," David Axelrod, Edwards' media consultant, told Fox News.

Saying Kerry's campaign has been pouring money into South Carolina, Axelrod added, "we've had to concentrate there, but we're competing in Oklahoma, New Mexico and Missouri -- we expect to have a very good day on Tuesday."

Dean burned through much of the $41 million he raised hoping to score a knockout in early tests.

"We took an enormous gamble and it didn't work," he said Sunday.

Dean said he wasn't ready to leave the race and was focused on winning delegates. But he acknowledged that he won't linger on if it became clear the nomination was out of reach.

Meanwhile, Lieberman touted the endorsements of newspapers in Seattle and South Carolina.

"What this says is I have national support," he said.

Fox News' Molly Henneberg and The Associated Press contributed to this report.