(TAMPA, Fla.) -- Mitt Romney accused Newt Gingrich Monday night of "influence peddling" during his time as a consultant for Freddie Mac, a sharp attack from the one-time front-runner that reflected the close race for the Republican nomination.
The showdown between Romney and Gingrich at the latest Republican presidential debate -- eclipsing the two other candidates -- wore on for so long that at one point, the debate's moderator had to cut them off to take a commercial break.
Romney started out by sharply criticizing Gingrich over his time as Speaker of the House in the 1990s, then turned his criticism to Gingrich's work with mortgage giant Freddie Mac.
"I don't think we could possibly retake the White House if the person who's leading our party is the person who's working for the chief lobbyist of Freddie Mac," Romney said.
But Gingrich countered with his trademark direct style, saying, "You've been walking around this state saying things that are not true."
He defended his role as a consultant to the mortgage giant by arguing that he wasn't lobbying, per se, but rather was openly advocating for Medicare plans.
"Here's why it's a problem," Romney said. "If you're getting paid by health companies...that can benefit from a piece of legislation, and you then meet with Republican congressmen and encourage them to support that legislation, you can call it whatever you like. I call it influence peddling."
The debate in Tampa, Fla., began on a decidedly negative tone and reflected the tension between Romney and Gingrich after the ex-speaker dominated the early front-runner in the South Carolina primary over the weekend.
The candidates spent the first portion of the debate going over personal issues, not national ones. Romney, for example, was questioned about his tax release, which was due within hours, and said he wouldn't follow his father's lead and release 12 years' worth of returns.
Romney also turned the questions about his taxes into a riff on his plan to lower taxes, and he told Gingrich that under the ex-speaker's plan, he would pay nothing in taxes because all his income comes from investments.
Gingrich replied by suggesting that he'd be fine with that, "if you created enough jobs doing that."
There were two other candidates at the debate -- Rick Santorum and Ron Paul -- but neither got much time in the spotlight.
Paul told the debate's moderator, NBC's Brian Williams, that he has "no plans" to run for president as a third-party candidate if he doesn't win the Republican nomination.
Santorum, meanwhile, continued to try to portray Romney and Gingrich as too moderate by tying them to the policies in President Obama's health care program.
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