Mitt Romney's campaign has made a practice of tearing down fellow Republicans in the race for the presidential nomination, but now he's coming under heavy assault himself as President Barack Obama's team revs up its campaign for the November election.
With Romney forecast to win Tuesday's primary in Wisconsin, a victory that would all but end the Republican nomination battle, Vice President Joe Biden began the Democratic attack on Sunday, calling Romney "out of touch" with the lives of middle-class Americans. Secretary of State Hillary Clinton criticized the former
Massachusetts governor for holding backward-looking views on foreign policy, and Biden said he was "stuck in a Cold War mentality."
Even so, a fresh set of prominent Republicans rallied behind Romney as the contest shifts from primary elections to win the nomination to the real contest for the White House.
Obama is vulnerable in his bid for a second White House term, weighed down by the economic suffering of the Great Recession. But his prospects improved as the Republicans engaged in a prolonged and bitter nomination fight and the economy showed signs of a sustained recovery.
Romney still hasn't convinced a defiant Rick Santorum to bow out of the Republican contest. The former Pennsylvania senator said he was not giving up just because the Republican party establishment believed voters "need Mitt Romney shoved down their throats."
The Wisconsin vote will be Santorum's last chance, however, to prove his strength in the US heartland, where he's said he can challenge Obama but where Romney has beaten him consistently.
Having devoted more than a week to campaigning across Wisconsin, Santorum is scheduled to return to his home state, Pennsylvania, the day before the Wisconsin contest. With Pennsylvania's primary more than three weeks away, that's an indication the conservatives' favorite may be in retreat.
Party heavyweights were pushing to end the contest.
"I think the chances are overwhelming that (Romney) will be our nominee," Senate Minority Leader Mitch McConnell said on Sunday. "It seems to me we're in the final phases of wrapping up this nomination. And most of the members of the Senate Republican conference are either supporting him, or they have the view that I do, that it's time to turn our attention to the fall campaign and begin to make the case against the president of the United States."
Rep Paul Ryan, the influential chairman of the House Budget Committee, spent the weekend at Romney's side campaigning in his home state of Wisconsin. The state's first-term US senator, Ron Johnson, endorsed Romney on Sunday.
With losses piling up in other industrial states like Ohio, Michigan and Illinois, Santorum acknowledged the results in Wisconsin on Tuesday will send a "strong signal" about the direction of the Republican contest. Maryland and Washington, DC also hold contests that day.
At the same time, the Obama camp was not wasting any time in taking the attack to Romney.
"I think Gov Romney's a little out of touch," Biden said. "I can't remember a presidential candidate in the recent past who seems not to understand, by what he says, what ordinary middle-class people are thinking about and are concerned about."
Obama's team also seized on Romney's foreign policy inexperience, with Clinton taking on Romney's comment that Russia is America's "No 1 geopolitical foe."
"I think it's somewhat dated to be looking backwards instead of being realistic about where we agree, where we don't agree," Clinton said.
Said Biden: "He just seems to be uninformed or stuck in a Cold War mentality. It exposes how little the governor knows about foreign policy."
With about half of the state-by-state Republican nominating contests complete, Romney has won 54% of the delegates at stake, putting him on track to reach the threshold 1,144 national in June, well before the Republican National Convention in August.