INDEPENDENCE, Iowa — Republican presidential contender Newt Gingrich called upon President Obama to forgo his federal salary in 2012 because he will spend much of the year campaigning. He also questioned the president’s knowledge of the Constitution and derided his ability to work with Congress.

View Photo Gallery: The PostPolitics team used the iPhone app Instagram and the tag #2012Unfiltered to document the week leading up to the Iowa caucuses.

“The comments I heard this morning were outrageously unconstitutional,” Gingrich said, referring to news reports about the president’s plans to push ahead with an agenda this year with or without Congress’s help. “Are they serious about this? As I understand it, they said they were going to govern without the Congress for the next year? This is technically impossible. This is like a kindergarten play.”

Gingrich turned his attention to the president at a moment when he is struggling to regain momentum within the Republican field. On the eve of the Iowa caucuses and in the final throes of an eight-day bus tour across Iowa, Gingrich has been pummeled by negative TV ads, but he said he is resolved to continue on to New Hampshire, South Carolina and Florida no matter what the outcome Tuesday.

“I don’t think I’m going to win,” Gingrich said. “If you look at the numbers, that volume of negativity has done enough damage.”

But he added: “Whatever I do tomorrow night will be a victory, because I’m still standing.”

Gingrich also laid out a starker contrast with Romney than he has to date, signaling clearly exactly what the tenor of his campaign — and his new TV ads — will be in the next few states as he tries to turn his fortunes around.

“Here we have a conservative who knows what he’s doing who was with Ronald Reagan at a time when Romney was an independent We have a conservative who in fact was with George H.W. Bush at a time when Romney was a Democrat voting for Paul Tsongas. You have a conservative who wrote the Contract With America at a time when Romney repudiated it. You have a conservative whose record of controlling government spending is dramatically better than Romney’s, and you have a conservative who voted against tax increases while Romney as governor raised taxes.”

He added: “I think that message is a very simple contrast. If that message sinks in, the natural weight of the Republican Party, from every election since 1964, will also sink in.”

Gingrich spoke after posing for pictures in front of Big Bud, the world’s largest tractor, at a farm exhibit here Monday morning. He appeared far healthier than he had the previous three days, when he was battling a flu that left him lethargic and watery-eyed — and presented an unfortunately resonant image for the declining fortunes of his campaign. Between bouts of illness, Gingrich has insisted on sticking with a rigorous campaign schedule, spokesman R.C. Hammond said — even as his wife, Callista, and aides used gobs of hand sanitizer and kept Gingrich segregated on the bus they’ve shared across Iowa.

Gingrich continued spreading the message that he is the most experienced, truest conservative best positioned to bring real change to Washington.

“Really effective presidents are educators and communicators more than they are managers,” he told a middling crowd of a few dozen at the Heartland Acres Agribition Center. “The first job as president is to communicate with the American people where we’re going, why we’re going there, why it’s the right thing to do, so that the American people can help get it done. If you can’t do that as president, you can’t effect change.”

Gingrich heads into Tuesday’s caucuses having slipped dramatically from first place to fourth, according to a Des Moines Register poll released late Saturday. He attributed the slide exclusively to the barrage of negative TV attacks, most of them financed by an independent super PAC supporting Mitt Romney, a former Massachusetts governor. Gingrich said Sunday that he has been “Romney-boated,” and he said he believes Romney would buy the election “if he could,” and that “anyone who lies as a candidate will lie as president.”

Gingrich also signaled that he plans to fight fire with fire in the next few nominating contests, promising to air tougher contrast ads against Romney and to defend the attacks against him. The change in tone is sure to have an effect on a super PAC working on Gingrich’s behalf, too; last week, Gingrich said he would “disown” any independent group that ran negative ads, but that directive seems to have changed.


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