Updated: 4:42 p.m.

Obama campaign manager Jim Messina and adviser David Axelrod downplayed former Massachusetts Gov. Mitt Romney’s Super Tuesday wins in a conference call today, suggesting that the GOP frontrunner is limping to victories while continuing to pile up baggage for the general election.

Axelrod and Messina said Romney’s narrow victory over former Sen. Rick Santorum (Pa.) in Ohio, built on a wave of negative attack ads, does not portend success in November. Axelrod said Romney hasn’t been able to pull away from Santorum and former Speaker Newt Gingrich (Ga.), and likened the GOP primary to a “death march.”

A GOP operative noted, however, that Axelrod used the same “death march” line in March 2008 to describe the battle between then-Sen. Barack Obama and Hillary Rodham Clinton.

Axelrod accused Romney of a “timid” response to talk-radio host Rush Limbaugh’s comments last week in which he called Georgetown University student Sandra Fluke a “slut” and a “prostitute” for supporting insurance coverage for birth control at religious institutions.

Romney is “afraid to challenge the de facto boss” of the GOP, Axelrod said. If Romney doesn’t have the strength to stand up to strident voices in his party, “How are you going to stand up to [Iranian President Mahmoud] Ahmadinejad?” he asked.

Messina and Axelrod said they are concerned about a potential wave of independent spending by super PACs against the president, which Messina said could top $500 million. “We have to get ready for it,” he said.

“We would be insane not to be worried about that,” Axelrod said. “I believe all things being equal we will win this election, but money does matter.”

Axelrod and Messina also noted Romney’s poor showing in polls of Latino voters — just 14 percent of likely Latino voters in a recent Fox News poll said they would support Romney versus 70 percent who said they would support the president. Axelrod said Romney’s hard-line stance on immigration, including his embrace of Arizona’s immigration law, has done “real and lasting damage.”

Romney won’t be able to “wipe the slate clean” once the primary is over, he said. “We’re going to hold him to his positions.”

The Romney campaign accused the Obama campaign of trying to avoid the president’s own weakness.

“President Obama and his campaign will say anything to try to distract from his abysmal record as president and the fact that his own party is rejecting him,” said Romney spokeswoman Andrea Saul. “President Obama was on the ballot in Oklahoma and received just 57 percent of the vote in the Democrat primary and, even in Boston, fully 10 percent of voters who cast Democrat ballots left it blank for president and refused to vote for President Obama.”