On Saturday, presumptive Republican presidential nominee Mitt Romney will deliver the commencement address at Liberty University, the nation's largest evangelical university. The speech will be attended by nearly 35,000 people, and it will give him a chance to win over a huge constituency that, up until recently, has been lukewarm about his campaign.

Case in point: Last fall, the Rev. Robert Jeffress created a huge stir when he said that Romney, a Mormon, is a member of a religious cult and "a conservative out of convenience." But now, Jeffress, who pastors First Baptist Church of Dallas, says he's fully behind the candidate.

"I think there's a realization among Christians that Jesus isn't on the ballot this year," says Jeffress, "and so, I mean, many times, voting is voting for the lesser of two evils."

President Obama shifted that balance dramatically when, earlier this week, he announced that he supports same-sex marriage.

"This has brought a new dynamic into the election, and it really is a gift to Gov. Romney from President Obama," Jeffress says.

Becoming Evangelicals' First Choice

Even before Obama's statement, evangelicals favored Romney over the president by 3 to 1, chiefly because they so dislike the president, according to a new poll by the Public Religion Research Institute. But can Romney turn that antipathy into enthusiasm for his own candidacy? Experts say that in order to win the election, Romney will not just have to satisfy evangelicals — he will have to thrill them.

"Social conservative voters in this election are not going to stay home," says Tony Perkins, president of the Family Research Council. "But the question is: When they drive to the polls, will they be driving a Suburban that's packed with friends and neighbors that they influenced, or will they be driving themselves in a so-called Smart Car?"

That's the question facing the faithful at First Baptist Church of Dallas, Jeffress' 10,000-member megachurch. Several people said Romney was their second, third or fourth choice. They're wary of him because, they say, he belongs to a religious cult; he was once pro-abortion rights and he was governor of Massachusetts when the Supreme Judicial Court ruled that same-sex marriage was legal (though Romney vehemently opposed it).

"I was open to Michele Bachmann, I was open to Rick Santorum, Rick Perry, those guys that I thought came out of that more conservative base," says Roy Sparkman, a former district judge. "But now that we're here, I'm going to be a Romney supporter."

Vera Strickland, a homemaker, says she's voting for Romney because she doesn't want a repeat of 2008, when millions of Christians stayed home rather than vote for John McCain.

"This is a call to arms," Strickland says. "It's a wake-up call to Christians that whether or not we like the choices, we must make a choice. And people need to wake up and realize if you want freedom, go vote."

But Mark Lavvorn has some residual distrust about Romney's commitment to conservative causes like traditional marriage and opposition to abortion.

"Mitt Romney is very smooth, very calculated — some would even describe him that way to a fault," Lavvorn says. "And I think he has some distance to go to convince the evangelical that he is genuine, that he is sincere in these issues."

Romney may have the chance to do just that when he gives the commencement address at Liberty University this weekend.

'A Golden Opportunity'

"Gov. Romney has a golden opportunity to make peace with evangelical Christians," Jeffress says of the speech. He says Romney will have an opportunity to hammer home the culture war themes that are so dear to religious conservatives — and he should be careful not to blow it.

"I think if Gov. Romney simply punts on this and says, 'Well, I'm going to focus on the economy and jobs, and leave all this other stuff alone,' I think he is going to absolutely squander this tremendous opportunity," Jeffress warns.

University of Akron political scientist John Green says Romney has an advantage over John McCain in 2008. Back then, evangelicals didn't know how much they disliked Barack Obama — now they do. But Green notes that if evangelicals want to have influence in a Romney administration, they need Romney as much as Romney needs them. And so far, they've snubbed him.

"Evangelical voters essentially backed other candidates in the primaries, so they need to mend some fences and strengthen their ties with [Romney]," Green says. "But of course the [presumptive] nominee will need them in the fall, and he's got to find ways to strengthen his relationship with them as well."

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