DES MOINES, Iowa (CNN) -- Former Sen. John Edwards dismissed plans of fellow Democrats as "fantasy" while Republican contender Mike Huckabee blasted his leading rival, Mitt Romney, as "dishonest" Sunday.
Sunday Republican presidential contender Mike Huckabee called his rival Mitt Romney "dishonest."
Polls indicate a close race among both parties ahead of Thursday's Iowa caucuses, the first contests of the 2008 presidential race.
Romney has been blasting Huckabee's record on crime and taxes as governor of Arkansas in television ads in the last days of the race.
"If a person is dishonest in order to get a job, do you believe that he will be honest if he gets the job? I think that's a serious question people ought to be raising at this point," Huckabee told NBC's "Meet the Press."
He also suggested he would not support Romney should the former Massachusetts governor beat him to the GOP nomination.
With the two men locked in a statistical dead heat atop the latest Iowa polls, Romney has been airing television ads criticizing Huckabee for raising state spending, backing in-state tuition for illegal immigrants at state colleges and granting more than 1,000 pardons and commutations.
Huckabee has said the claims are taken out of context, and hit back by questioning the sincerity of Romney's opposition to abortion -- which was covered by the state health care program Romney pushed through in Massachusetts. Watch Huckabee fire back at Romney »
Romney's camp says state law requires any subsidized health care plan to cover reproductive health care, and Romney said he was simply pointing out contrasts between his position and those of his opponents.
"An ad that describes where I stand on an issue and where my opponent stands on an issue I think is totally appropriate," he told reporters in the Mississippi River valley town of Columbus Junction. "What I don't do in my ads is attack, on a personal basis, my opponent."
Published polls show close races in both parties in Iowa. A Mason-Dixon survey of likely participants, released Sunday, showed Huckabee and Romney were locked in a statistical dead heat on the Republican side.
An American Research Group poll released Saturday gave Romney an edge over Huckabee for the first time in over a month, while the last CNN-Opinion Research Corp. poll, conducted December 14-18, put Huckabee over Romney by an eight-percentage-point margin.
The remaining GOP candidates -- Sen. John McCain of Arizona, former Tennessee Sen. Fred Thompson, former New York Mayor Rudy Giuliani, Texas Rep. Ron Paul, Rep. Duncan Hunter of California and commentator and former State Department official Alan Keyes -- trail behind Romney and Huckabee in Iowa polls.
But Thompson, a former U.S. senator and actor in the television drama "Law And Order," told CNN's "Late Edition with Wolf Blitzer" that he had "a decent chance" of pulling a second-place showing out of the caucuses.
"While all this hullabaloo is going on around me and everybody's attacking each other and everybody's talking about process and who's got the most political ambition to drive them, I'm just going to stay steady up the middle with the same conservative, common-sense message that I've had and what I've always been in my political life from day one," he said.
Among Democrats, Edwards, Sen. Hillary Clinton and Sen. Barack Obama of Illinois had virtually identical levels of support in Sunday's Mason-Dixon poll. Saturday's ARG survey gave Clinton a narrow lead over Obama and Edwards, while the CNN poll found a four-point spread among the top contenders, led by Clinton.
Edwards, the Democrats' vice presidential nominee in 2004, told CBS' "Face the Nation" on Sunday that Democrats would face "an epic fight" in pushing for reforms such as universal health care if they reclaim the White House, and argued that he, as a longtime plaintiff's lawyer, was best suited to wage those battles.
He said Obama "has this philosophical view that you can sit at a table with drug companies, oil companies and insurance companies and negotiate with them, and somehow they'll just voluntarily give their power away -- and I think that's a complete fantasy. It will never happen."
Meanwhile, he said, Clinton "defends the system in Washington" that Edwards blasts as "rigged" by corporate interests.
"I don't think you can take these people's money, the lobbyists, the PACs, et cetera, and sit at a table and make a deal with them," he said. "I think if that worked, it would have worked a long time ago."
Edwards also used the term "fantasy" to describe Clinton's statement that if she became president, her husband -- former President Bill Clinton -- would have no official role in her administration. Edwards said he would put the former president to work if he were elected, "providing help around the world and with leaders around the world."
Clinton has touted her experience in the White House during her husband's presidency, even though she concedes she did not attend top-level meetings such as National Security Council sessions. But she told ABC's "This Week" that she had "direct access to all of the decision-makers."
And she touted her experience on the business end of criticism from political opponents for more than a decade and a half.
"What people know about me is that I've been vetted and I've been tested," said Clinton, who led an unsuccessful effort to provide universal health care during her husband's first term.
"I've been on the receiving end of a lot of Republican incoming fire for 16 years, and I have, much to their dismay, survived and thrived."
Obama, meanwhile, used the last weekend before the caucuses to tell Iowa voters that he was ready to "play some offense" against Republicans in the fall.
"The latest polls show me beating every Republican," the first-term senator said during a rally in Newton, Iowa, about 35 miles east of Des Moines. "I beat Rudy, Mitt, Fred, John, Mike. They didn't poll Ron Paul, but I would have probably beat him."
But one of the other Democrats in the field, Delaware Sen. Joseph Biden, told CNN that nominating a candidate now running in the second tier of candidates -- such as himself or his Connecticut colleague, Sen. Christopher Dodd -- would lower the "boiling point" of the campaign "a great deal."
"We both have long records of cooperating extensively with Republicans without yielding one bit on our principles," said Biden, the chairman of the Senate Foreign Relations Committee.
Biden, Dodd, Ohio congressman Dennis Kucinich, New Mexico Gov. Bill Richardson and former Alaska Sen. Mike Gravel round out the Democratic field. E-mail to a friend