WASHINGTON — Our presidential candidates go through a rigorous, even brutal, screening process — grueling campaigns across four time zones, endless debates, alarming ethnic foods. We see how they handle themselves under stress, explaining away wacky preachers, little autobiographical fictions, long-ago land deals, fending off a lesbian's request to walk her down the aisle on her wedding day.

There's not too much we don't know about them. We've seen their tax records and, in the case of John McCain's medical records, we perhaps know a little too much. You can't say our presidential candidates haven't been thoroughly vetted.

But what about the vice presidential candidates? Rather than being rigorously screened, they are presented to us, after a selection process pretty close to voodoo, as a fait accompli.

Our current president, George Bush, paid his dues in the primaries and caucuses. But how did we get Vice President Cheney, who sometimes declares he isn't vice president of the United States at all but president of the U.S. Senate?

Assured of the nomination in 2000, Bush appointed a search committee headed by Dick Cheney to come up with his running mate, and to no one's surprise but the electorate's, the committee came up with — Dick Cheney. The first Bush's vice president, Dan Quayle, was suddenly unveiled to the public on a riverboat.

Vice presidents are important, at least in the abstract. Truman, Johnson and Bush senior all ascended to the White House from the vice presidency. Jerry Ford, the accidental vice president, became the accidental president. If Vice President Al Gore had run a decent campaign, Vice President Joe Lieberman might now have the 2008 Democratic presidential nomination well in hand instead of roaming around political no-man's land.

Lieberman, by the way, has been "mentioned" by the Great Mentioner as a possible running mate with his good friend McCain. And that brings up a curious point about the vice presidency. To actively seek that post is the kiss of death. In our modern version of Plato's republic, anybody who visibly wants to be vice president is too crazy to have it. But of course politicians do want it — Truman, Johnson, Bush, etc. — and the trick is to look available without looking interested.

But that reticence doesn't apply to the presidential candidates. It's in their interest to have their camps float the names of as many people as possible as running mates. It's a cost-free form of flattery and there's no commitment involved because the recipient, of course, is forced to deny any interest. There will be some ingrates, but you always have those in politics.

MSNBC has a bracket pool, rather like March Madness, of vice presidential possibilities. There are 32 names on the list. Here's one. Rob Portman. You remember. Played Queen Amidala in "Star Wars"? No, just kidding. That was Natalie but had you going for a second, didn't I? Rob Portman is a former White House budget director, special trade rep and member of Congress, great qualifications, but nobody's ever heard of him.

On the Democratic side, Barack Obama and Hillary Clinton can't even mention a vice presidential candidate — even though one of them will have to have one — for two reasons: It looks overweening without the nomination locked up; and the mere mention could smack of desperation: "OK, you won. I guess I'll have to settle for the two spot."

In a new wrinkle in the vice presidential selection process, McCain had Charlie Crist, Bobby Jindal and Mitt Romney out to his cabin in Arizona for a cookout. Just a picnic among friends, we're told, as if the governors of Florida and Louisiana and former governor of Massachusetts just happened to be roaming around Sedona when they got a yen for barbecue.

It's probably a desirable trait in a running mate to be able to eat ribs without dribbling sauce on his shirt. But here's the really weird thing, and they all swear it's true, and they're probably right: They never talked about the vice presidency.

Contact Dale McFeatters at [email protected].