Projecting the confidence of a front-runner, former Massachusetts Gov. Mitt Romney swept into Iowa on Tuesday ahead of next week's presidential caucuses, looked past his Republican rivals and accused President Obama of "misguided policies and weak leadership."
"Mr. President, you have now had your moment. We have seen the results. And now, Mr. President, it is our time," Romney said.
Romney unleashed his attack on Obama as other Republican candidates vied to emerge as his principal conservative rival in the long march of primaries that follow next Tuesday's caucuses.
Former House Speaker Newt Gingrich, slipping in recent polls, said he would not vote for Rep. Ron Paul if the Texan is the party's opponent against Obama next fall. In an interview on CNN, he said Paul holds "views totally outside the mainstream of virtually every decent American," adding that Paul believes that it doesn't matter if the Iranians have a nuclear weapon.
There was no immediate response from Paul, who has run television ads critical of Gingrich.
Meanwhile, a 2006 memo by Gingrich showed that he once praised the health care law Romney put in place in Massachusetts as governor. Romney's rivals, including Gingrich, have tried to tar him for enacting the series of health care changes.
Gingrich called the law "the most exciting development of the past few weeks" and one with "tremendous potential to effect major change in the American health system."
The memo from Gingrich's Atlanta-based Center for Health Transformation noted shortcomings in the law but went on to note that "we agree entirely with Gov. Romney and Massachusetts legislators that our goal should be 100 percent insurance coverage for all Americans."
Gingrich spokesman R.C. Hammond said the memo was "old news that has been covered already."
"Newt previously supported a mandate for health insurance and changed his mind after seeing its effects," Hammond said. "The real question is why 'Mitt the Massachusetts Moderate' won't admit that health insurance mandates don't work."
In Dubuque, the first stop of Gingrich's bus tour through the state, he said his economic proposal for an optional flat tax as well as the elimination of all capital gains taxes was a more pro-growth approach than Romney's prescription.
"I've been a conservative all my life," he said. He called Romney a "Massachusetts moderate who campaigned to the left of Teddy Kennedy."
Texas Gov. Rick Perry also set out on a bus tour of Iowa in hopes of resurrecting his candidacy. "My idea of gun control? Use both hands," he said at on campaign stop. He also toughened his position on abortion, saying that it should be prohibited in all cases.
In a radio interview, former Pennsylvania Sen. Rick Santorum said Romney had "sort of gotten a pass" when he said in a recent debate that he had done all he could as Massachusetts governor to block same-sex marriages in the state.
Rep. Michele Bachmann of Minnesota, who also was on a bus tour of Iowa, saw herself as the rightful Romney alternative.
"I am the only consistent conservative in the race and the only candidate with the proven leadership and experience to create more American jobs and repair our economy," she wrote in an email seeking donations for her underfunded candidacy.
Recent public opinion polls suggest that Paul is Romney's likeliest threat in Iowa. The Texan is due in the state today.