If the audience at Thursday’s Faith and Freedom Coalition conference were choosing Mitt Romney’s vice presidential nominee, the decision, in the words of one attendee, would be “a no-brainer.”

Sens. Rob Portman (R-Ohio) and Marco Rubio (R-Fla.) spoke in back-to-back speeches before a luncheon crowd of about 200 people at the coalition’s annual meeting at the Renaissance Hotel.

And while the even-tempered Portman received a warm reception for a speech that focused heavily on his family and personal faith, it was Rubio who electrified the crowd, drawing repeated rounds of cheers and applause with an address heavy on soaring rhetoric about American exceptionalism.

“What’s at stake is our very identity,” Rubio told the crowd, which included only a fraction of the 1,500 attendees expected over the course of the three-day summit.

Sen. Marco Rubio (Haraz N. Ghanbari/Associated Press)

“They literally pit Americans against each other by design for purposes of winning an election, and that’s never been who we’ve been,” he said.

Urging the crowd not to allow “misinformation to become fact,” Rubio contended that when it comes to social conservatives’ arguments about religious freedom, “it’s never been about imposing our values on others.”

By the same token, he argued that constitutional conservatism is “not about leaving people behind.”

“We believe we’re mandated by our faith to care for those who are less fortunate than ourselves,” he said to applause.

And he argued that conservatives are “not anti-government.”

“We believe government is an important institution in society,” he said. “It’s just not the most important institution in society.”

Rubio — who this month is launching a tour for his memoir, which was available for sale at the event — eluded members of the media as he left the hall, in contrast to Portman, who fielded a range of questions from a gaggle of about 30 TV and print reporters.

When several reporters peppered Rubio with questions as he exited the ballroom, he responded with a note of exasperation.

“Guys. Come on, man,” he said as he was ushered down the hall.

Sen. Rob Portman (Melina Mara/The Washington Post)

“We shouldn’t stray away from the fact that our Judeo-Christian heritage is part of who we are,” Portman said at one point. At another, he recited a Bible verse.

He opened by telling attendees that he believes public service is “a noble profession when it’s practiced with humility,” and told of several instances during which he took time away from public life in order to be with his family, including in the aftermath of his mother’s diagnosis of cancer.

“Like (my parents), my faith sustains me,” he said. “Like them, I pray every day. Sometimes, I pray for guidance on Capitol Hill. That’s needed. Sometimes, I’m not sure the message I’m getting, but I’m trying. But I’ve got lots of room to grow in my faith journey.”

He spoke of his decision to run for Senate in 2010 and said that at the time, his 14-year-old daughter, Sally, encouraged him to run.

“Dad you know what? You need to get out of the house a little bit more,” Portman said his daughter told him.

A few moments later in his speech, Portman turned his fire — and the quip from his daughter — on Obama.

“The president gave us a glimpse into the failed philosophy he has chosen last week when he proclaimed that the private sector was doing just fine. He needs to get out more,” Portman said to laughs.

The contrast between Rubio and Portman was evident in their introductions as well as in the reactions of attendees.

Portman was introduced by former Ohio secretary of state Ken Blackwell, while Rubio was introduced by Ralph Reed, the founder of the Faith and Freedom Coalition. Reed hailed Rubio’s come-from-behind win in the 2010 Florida Senate GOP primary and praised the senator as “one of the greatest talents and one of the most transformational figures” on the national stage.

Those words appeared to resonate with attendees, several of whom said after the luncheon that they believed Romney should pick Rubio over Portman hands-down.

“I think I’d have to say Rubio,” said Ivy Bonk, a 50-year-old Delaware-based political operative. “He was awesome. I think it’s just, when he was being introduced, they were talking about being transformational. And so, he just has a way of inspiring. And you know, when they told the story about the race — he was 30 points out, and how he overcame. I think he can transfer that to the American people very well.”

Ginger Bigelow, a 59-year-old insurance company worker from western Maryland, said with a laugh that her choice was “Rubio all the way.”

“Well, if I can be candid, I mean, he’s Hispanic; we’re going to need that part,” she said. “Romney’s going to need all the help he can get. He’s young, so he’s going to, I think, attract the younger people. ... He’s obviously come from not a lot and made it, so I think he’s a perfect choice. I really do.”

Gus McDowell, a 70-year-old retiree from Greensboro, N.C., called it a “no brainer” for Romney to pick Rubio in the veepstakes — and that many conservatives in North Carolina already believe that the Florida senator will be Romney’s choice.

“He has a great understanding of what the American dream is all about, and being an American. ... He has the charisma,” McDowell said. “He has the agility. He’s at the age now that he can do a whole lot for this country. Secular-wise, religious-wise, and also economical-wise. So to me, right now, he’s one of the best ones that we have, and we believe that he can really get it done.”

“I’m from North Carolina,” he added. “We in North Carolina feel that Rubio is going to be the person.”

This post has been updated since it was first published.