WASHINGTON (Reuters) - President Barack Obama and Republican challenger Mitt Romney fired a series of sharp attacks at each other on Wednesday as they opened a seven-month battle for the White House that is getting ugly fast.
Both campaigns moved quickly to frame the choice for voters one day after Romney's chief rival, conservative Rick Santorum, dropped out, giving the former Massachusetts governor a clear path to the Republican nomination to challenge Obama in November's election.
On cue, the Obama campaign released a video of Romney's more awkward moments on the campaign trail and again portrayed him as a wealthy, out-of-touch conservative.
Romney attacked Obama's economic leadership as a failure and described him as a throwback to the era of "big-government" Democrats.
The exchanges were a sign of things to come in a general election fight for the White House between two candidates who have shown they are willing to throw a punch.
Obama's campaign video entitled "Memories to Last a Lifetime" reminded voters of potentially embarrassing statements from Romney in the Republican primary campaign. Among them were his declaration that "corporations are people" and his claim to have been a "severely conservative" governor of Massachusetts.
"Mitt Romney: A severely conservative nominee. Remember that," the video says, pre-empting any move by Romney to tack to the center to win independents in the coming months.
For the second consecutive day, Obama promoted the Buffett Rule, a plan to ensure that millionaires like former executive Romney pay at least 30 percent income tax.
At an event in the White House, Obama said the Republican Party had moved to the right and recalled the belief of former President Ronald Reagan, a Republican and conservative icon, that the wealthy should pay their fair share.
"What Ronald Reagan was calling for then is the same thing we're calling for now - a return to basic fairness," Obama said at the event, which featured a number of millionaires and their secretaries.
Congress will take up the Buffett Rule, named for billionaire investor and Obama supporter Warren Buffett, next week but the timing of Obama's comments also is part of his portrayal of Romney as an out-of-touch elitist.
The Obama campaign placed a digital calculator on its website allowing Americans to see how their tax rate compares to the 13.9 percent rate Romney paid in 2010. He paid that low rate because most of his income was from investments rather than wages, which are taxed at a higher rate.
Romney, a former head of a private equity firm who has touted his business background, said Obama was trying to change the subject from his poor handling of the economy.
"He's really trying to divert from the failure of his record, which is that he has not created jobs," Romney said in an interview with Fox News. "I think this president represents a throwback to the old-style Democrats of the past: big government, welfare state Democrats."
Romney's campaign plans to focus on painting Obama as an incompetent steward of a stuttering economy.
But with the primary competition behind him, Romney still must rally distrustful conservatives and unite a party with fresh memories of a divisive nominating battle that featured millions of dollars in negative attack ads from Romney and his campaign allies.
Romney also must repair his image with women voters, which polls show suffered during the primary campaign. Democrats were quick to criticize on Wednesday when three Romney advisers were unable to say during a conference call with reporters whether Romney backed a law signed by Obama on equal pay for women.
The Romney campaign later said he backed the law and released a flood of statements attacking Obama's record on creating jobs for women.
"Of course Mitt Romney supports pay equity for women. The real question is whether President Obama supports jobs for women," said Romney campaign spokeswoman Amanda Henneberg.
Romney said he was confident the party would unite as the campaign moved forward and said he was not concerned about the Obama campaign's charges that he is out of touch with everyday Americans.
"We are getting started with a general election campaign and people will get to know me better and they'll get to know him better as well and they'll look at his record," Romney told Fox. "But the person I am out of touch with is Barack Obama; I am in touch with the American people."
Santorum did not endorse Romney when he suspended his campaign but Santorum adviser John Brabender said on MSNBC the two former rivals would meet to discuss their differences.
"They have to talk about some things. Rick will be a team player," Brabender said. "There are still some discussions they have to have, healthcare is one of them."
Santorum harshly criticized Romney for his support as Massachusetts governor of a state healthcare plan that became a precursor for Obama's federal overhaul.
"At the end of the day, we are all family," Brabender said of Republicans.
(Additional reporting by Matt Spetalnick, Doina Chiacu; Editing by Bill Trott)