McManus: And Romney’s veep choice is ...

The “Veepstakes” are on — but the smart money says they’re already over.

Like belles at a debutante ball, up-and-coming Republican politicians are lining up to campaign with Mitt Romney, hoping to catch his eye as a suitable choice for vice president. And Romney has an intriguing list of choices, some of them honest-to-God exciting.

There’s Sen. Marco Rubio, the “tea party” darling from swing-state Florida who just happens to be Latino. There’s Chris Christie, the volcanic (and rotund) governor of New Jersey. There’s Rep. Paul D. Ryan (R-Wis.), the perky author of the House Republican budget, who got along so well with Romney during the Wisconsin primary campaign that reporters began writing about “bromance.” And there’s Bob McDonnell, the flinty GOP governor of Virginia, who’s buying television commercials to tout his record even though he’s not running for anything this year. (So much for the Republican virtue of thrift.)

COMMENTARY AND ANALYSIS: Presidential Election 2012

With all those intriguing names in the mix, what’s Romney going to do? I hate to spoil the fun, but every Republican strategist I surveyed this week had the same answer: Romney’s almost certain to opt for the most boring, conventional choice possible, Sen. Rob Portman of Ohio.

Four years ago, a Republican nominee chose an exciting, fresh face for his running mate, and she promptly landed the campaign on “Saturday Night Live."This year, the no-drama Romney campaign, so buttoned up that it makes Team Obama look like an improv troupe, wants to avoid a rerun of the Sarah Palin Experience.

“We already tried sexy,” one GOP operative told me. “Sexy didn’t work.”

But wait a minute, I hear you saying. Rob who?

Robert Jones Portman, 56, junior senator from Ohio. A lawyer from the suburbs of Cincinnati, he won seven consecutive elections to the House beginning in 1993. He’s a budget guy — he served in the White House as PresidentGeorge W. Bush’s director of the federal budget — but he’s not a firebrand like Ryan.

“He is a very conservative guy with good manners,” Ted Strickland, Ohio’s former Democratic governor, told reporters this week. “That causes some people to think he’s a little more moderate than he is.”

Portman’s good-looking but no movie star. He’s personable but not dazzling. He’s virtually unknown outside his home state. In a recent national poll of Republicans, he landed at the bottom of the list, well behind Rubio, Christie, Ryan and McDonnell — not to mention former Secretary of State Condoleezza Rice, who topped the chart at 26%, and presidential primary runner-up Rick Santorum, who scored 21%. Portman has the support of less than one-half of 1% of Republicans, the CNN poll found.

But that simply doesn’t matter. A vice presidential candidate needs to do just three things for the ticket.

He or she needs to embody some quality the candidate needs help with, whether it’s youthful conservative energy (Sarah Palin), blue-collar empathy (Joe Biden) or just adult supervision (Dick Cheney). He or she needs to be smart enough to survive a debate with the vice presidential candidate from the other side, and steady enough to avoid gaffes that get in the way of the campaign’s message. (That’s why Palin was such a disaster for John McCain.) And, if possible, he or she should help the candidate carry an important state — although that’s optional (Palin wasn’t chosen for Alaska, nor Cheney for Wyoming, but Biden spent a lot of time in Pennsylvania, the state of his birth).

Portman would help Romney on all those counts. He’s a budget-savvy conservative who can talk about the economy, the only issue Romney really wants to highlight in the campaign. He’s experienced enough — and bland enough — to avoid gaffes. He’s smart enough to match or beat Biden in the vice presidential debate. (Portman played the role of Barack Obama in GOP debate preparation exercises in 2008, the role of John Edwards in 2004 and the roles of both Al Gore and Joe Lieberman in 2000.) And he might carry enough home-state appeal to help Romney prevail in Ohio, a swing state that he almost surely needs to win.

All the other potential candidates come with more flaws. Rubio, 40 years old and fresh from the Florida Legislature, is untested on the national stage; as a Cuban American, it’s not clear how many Mexican American votes he’d sway in the Southwest, and he might not even guarantee a win in Florida. Christie is a favorite of campaign reporters because of his New Jersey penchant for blunt, undiplomatic remarks, but that might be enough to disqualify him right there. Ryan would please the tea party, but he would also shackle Romney to the Ryan budget, which proposes turning Medicare into a voucher plan, an issue on which the candidate has tried to retain a bit of wiggle room. McDonnell is popular in Virginia, but outside the state he’s known mostly for promoting state-mandated vaginal examinations for women seeking abortions — an idea he abandoned after a nationwide outcry and not one the Romney campaign wants to spend much time on.

A business strategist from Harvard Business School and the Boston Consulting Group, where Romney started, would look at that field and say: Choose the one who best reinforces your agenda with the lowest degree of risk. If those are the criteria, the choice is easy: Rob Portman.