"His whole campaign was a fear-and-smear attack to make Romney unacceptable and to blame George Bush for anything that happened while Obama was president," Barbour said. "This was all personal: that Romney is a vulture capitalist who doesn't care about people like you, ships jobs overseas, is a quintessential plutocrat and is married to a known equestrian."
Barbour added: "An attack unanswered is an attack admitted to."
Had the criticism been shown to be false or unfair, the results might have been better, said Bill Bennett, an education secretary in the Reagan administration and an informal adviser to governors.
"We were in a big fight. We came with a knife; they came with a gun," Bennett said. "If Mitt Romney had responded and had we responded on his behalf — and had his campaign pushed back more forcefully — I think it would have been a different result."
Jindal, however, attributed Romney's loss to a lack of "a specific vision that connected with the American people."
"His campaign was largely about his biography and his experience," Jindal said. "But time and time again, biography and experience is not enough to win an election. You have to have a vision, you have to connect your policies to the aspirations of the American people. I don't think the campaign did that and as a result, this became a contest between personalities and — you know what? — Chicago won that."
Romney cast his loss in a different light, at least in a phone call Wednesday with top donors. He asserted that Obama won re-election because of the "gifts" the president had already provided to blacks, Hispanics and young voters and because of the president's effort to paint Romney as anti-immigrant.
"The president's campaign, if you will, focused on giving targeted groups a big gift," Romney said, citing immigration proposals aimed at Hispanics and free contraception coverage that appealed to young women. "He made a big effort on small things."
White House press secretary Jay Carney disputed Romney's assessment, telling reporters traveling with Obama to New York City on Thursday that policies allowing more young people to go to college or stay on their parents' health plans are good for the country and the economy.
"I think that view of the American people or the electorate and the election is at odds with the truth of what happened last week," Carney said.
Romney said his campaign, in contrast, had been about "big issues for the whole country." He said he faced problems as a candidate because he was "getting beat up" by the Obama campaign. He said the debates allowed him to come back.
The Republican nominee didn't acknowledge any major missteps and said his team had run a superb campaign.