By Candy Crowley, CNN Chief Political Correspondent
Washington (CNN) - Mitt Romney thinks a Wisconsin/Maryland/D.C. sweep Tuesday night will set him sailing to the nomination long before the August Republican convention.
Still, he's not about to own it.
Asked at a diner in Fond du Lac, Wisconsin whether he had made a vice presidential pick, Romney said no. "I'm not presumptuous enough because I'm not the nominee yet."
Rest assured someone inside Camp Romney is thinking about vice presidential picks. The candidate, though, follows a long line of almost-nominees who do not want to be caught publicly musing about a No. 2.
There is no such reticence in the rest of political world, where it is never too early to rush the season with a quick round of veepstakes.
Among the most frequently mentioned vice presidential possibilities:
- Virginia Gov. Bob McDonnell, a popular, media-savvy guy from the South, which has not been fertile territory for Romney. And Virginia is a swing state, which swung Obama-Biden in 2008.
But that McDonnell-signed Virginia law requiring women to undergo an ultrasound procedure before an abortion might not do much to close that giant Republican gender gap.
- If Romney has an authenticity deficit, New Jersey Gov. Chris Christie oozes it. Republicans love his in-your-face-ness, but part of the "authentic Christie" is a temper:
Christie once told a law student who argued with him at a town hall meeting, "Let me tell you something, after you graduate from law school, you conduct yourself like that in a courtroom, your rear end's gonna get thrown in jail, idiot."
After the man was removed, Christie told the audience that he tried to be patient, "and i think, 'Damn, man, I'm governor - could you just shut up for a second.' "
Christie may also have a geographic problem. An all-Northeast ticket might be a hard sell west of the Mississippi.
If Romney sees geography as important (and he might not), there are plenty of choices to balance out the "East Coast" thing.
- First among equals is U.S. Rep. Paul Ryan of Wisconsin, the brainy budget star of the House.
Downside: Ryan is the Republican face of Medicare reform, not a huge plus in an election year.
- U.S. Sen. John Thune of South Dakota is solid and versatile. He has the distinction of toppling Senate Minority Leader Tom Daschle in 2004.
- Two-term Indiana Gov. Mitch Daniels is regarded as a bright light in the party.
Still, all three declined chances to run for the top spot, so there are big questions as to why No. 2 would look better. So far, only Ryan has shown nuanced interest.
"I'm focused on doing my job. So it's just not my forte to get into that kind of speculation," he told me on Sunday.
- Also offering a change-up in geography and resume, U.S. Sen. Rob Portman of Ohio is a seasoned though not scintillating Washington veteran of Congress and the Bush administration.
- Louisiana Gov. Bobby Jindal also makes the cut. Though his star has been higher, Jindal still brings youth, diversity, party brand conservatism and a breadth of policy experience to the table - not to mention those Southern roots.
His endorsement of Rick Perry might not help. Just sayin'.
Here are some other people sometimes mentioned:
- New Mexico Gov. Susana Martinez has a trifecta of political assets. She is female, Hispanic and the governor of a swing state. Debits: Martinez is untested and unknown on the national scene as is South Carolina's Gov. Nikki Haley, whose name comes up from time to time.
There have been stumbles for both in their first terms, but they are sharp and know how to wield power. Still, the thinking in and around Camp Romney is that whoever they pick must be seen as having the resume and the chops to step into the No. 1 slot if necessary.
And finally, someone who is always mentioned:
- U.S. Sen. Marco Rubio of Florida is a tea party favorite, a rising star from a swing state and a Cuban-American, which could help build an inroad to the politically pivotal Hispanic community.
A senator for less than two years, he is also young and green and unwilling to play the veepstakes.
"My answer hasn't changed. I'm not going to be vice president," he said Thursday.
They almost always say things like that. Until they say yes.