Anchors on the major networks asked the same question and a stream of pundits predicted Romney's Mormon religion would be a significant hurdle.
Almost one year later, on Thursday, Romney withdrew from the race after suffering several big losses and facing an insurmountable challenge to beat Republican rival John McCain. The degree to which his faith contributed to that defeat may never be fully known.
It's clear, however, that Romney's belief in The Church of Jesus Christ of Latter-day Saints cost him in his presidential quest. Romney himself acknowledged that had he been a Baptist, for example, he may not have lost the Iowa caucuses - a devastating setback to his early surge strategy.
But Romney's Mormon faith also gave him a boost.
In fundraising, in drafting volunteers, in votes, Romney was able to reach out to a base of Mormons who responded in droves.
"It was a benefit organizationally and financially. He drew a lot of volunteers, a lot of money out of Utah, a lot of Mormons around the country," says Quin Monson, assistant director of the Brigham Young University Center for the Study of Elections and Democracy. "But it was a weakness in the voting booth, especially in Iowa."
Last year, Romney pulled $5.2 million out of Utah, his second largest state for contributions and a state where more than 60 percent of residents are Mormon. Much of that money came from donors who had never given to a candidate, and it set a new state record for donations to a single candidate in that amount of time.
The campaign set up call centers in Utah to phone potential voters in the early states, and many Utahns hit the road to campaign for Romney as well. Several Mormons from the Washington, D.C., area crammed into a van and went to help Romney in New Hampshire.
Romney's first victory came in the Wyoming caucuses, a win that Romney trumpeted after a second-place showing in Iowa and one he reminded voters of after he came in second in New Hampshire as well.
Tom Sansonetti, the 2008 GOP county conventions coordinator in Wyoming, figures Romney's faith probably helped him win at least four of the delegates there. "The Mormon element was beneficial in the western" half of the state, Sansonetti said.
Romney relied on a base of Mormons like other candidates fell back on their own bases for support, Sansonetti said. "It's just the same as being an African American helps Barack Obama and being a middle-aged woman helps Hillary Clinton. Everybody's got a base."
Romney won 's third win (after Michigan) came in then Nevada, where entrance polls showed a quarter of the caucus-goers described themselves as Mormon and those voters went for Romney almost universally. Romney would have won the state regardless of whether Mormon voters showed up, but he would have grabbed a smaller margin of victory.
"In the Mormon Belt, or whatever you want to call it, there was a tremendous amount of support from the church" faithful, said Jeff Hartley, a political consultant and former executive director of the Utah Republican Party.
But Romney's faith also spelled trouble throughout the campaign.
When the Boston Globe reported broke a story that Romney advisers had met with LDS Church officials ostensibly to tap into a network of Mormons to boost Romney's candidacy, Romney and the church denied any collaboration. But the news, true or not, raised further fears about Mormons, a faith viewed by some Protestant evangelicals as heretical, non-Christian or even a cult.
Romney tried to dismiss issues about his faith with a constant mantra that he was running to be commander-in-chief not "pastor-in-chief." He declined to discuss specific doctrines of his faith.
But when concerns carried on, Romney decided he must address his critics head on. In a much-heralded speech at the George Bush Presidential Library in Texas, Romney said Americans should look beyond differences among faiths to the shared values they embodied.
In the end, it may have convinced some voters, but not enough.
Iowa handed Romney his first loss, thanks to a huge turnout of caucus-goers who described themselves as evangelical or born-again Christians and backed Mike Huckabee, a Baptist preacher-turned-politician. Huckabee ran ads calling himself a Christian leader, refused to say whether the LDS Church was a cult and was quoted in The New York Times Magazine asking whether Mormons believe Satan and Jesus were brothers.
After his loss in Iowa, Romney acknowledged faith was a contributor.
"Mike had a terrific base as a minister - drew on that base, got a great deal of support, it was a wonderful strategy that he pursued effectively," Romney said. "Had I been a Baptist minister, I perhaps could have chosen a different path, but that wasn't the path that's available to me."
Rep. Steve King, an Iowa Republican who had originally backed rival Fred Thompson, says Romney was dinged for his faith.
"I think he was unjustly and inappropriately penalized for his religion," King said. "It was a factor" in his overall defeat.
Romney's Iowa loss meant he couldn't get a campaign bump heading into New Hampshire. Romney essentially skipped out of South Carolina, a state with a huge evangelical population and where fliers and comments attacking Mormonism had sprouted several times in the past year.
Concerns about voting for a Mormon may have also cost Romney victories in other southern states on Super Tuesday when Huckabee scooped up more delegates.
Romney had hoped that his faith would not materialize as the big hurdle political observers and polls had predicted.
"I don't think that the American people in the final analysis have shown that they care about the doctrinal differences between different faiths," Romney said told The Salt Lake Tribune between campaign stops in New Hampshire last year. "I think what is at the core of the American desire [is] to have a person of faith lead the country.'
Unfortunately for Romney, it appears the choice of that which faith still matters to some voters.