WASHINGTON - Tag. I'm not it.

Republicans considered to be up-and-comers are scrambling to declare a lack of interest in becoming Mitt Romney's running mate, taking themselves off the still-forming short list of would-be vice presidents. With Romney poised to win the GOP nomination in June, if not earlier, some of the focus has shifted to his pick for the No. 2 spot on the ticket. But no one is rushing forward and many of the top prospects are trying to shut down the conversation before it begins.

"I'm not going to be the vice president," Sen. Marco Rubio said Wednesday.

"If offered any position by Gov. Romney, I would say no," South Carolina Gov. Nikki Haley told The Associated Press a day earlier.

"I've taken myself off the list," former Minnesota Gov. Tim Pawlenty said recently.

"It's humbling, but I'm not interested," New Mexico Gov. Susana Martinez said.

It's not that bad of a job, is it? Well, it depends. John Nance Garner, who was President Franklin D. Roosevelt's vice president, described the job as "not worth a bucket of warm spit," among other characterizations.

Some of the would-be picks already have pretty good day jobs as governors: Mitch Daniels in Indiana, Bobby Jindal in Louisiana, Chris Christie in New Jersey and Bob McDonnell in Virginia. Rob Portman of Ohio and John Thune of South Dakota have seats in the Senate, and Paul Ryan of Wisconsin in the House.

Part of the dance is trying to appear uninterested in the role of designated attack dog and potential GOP front-runner for 2016 if Romney falls short in November. Part of it is also preserving a personal brand; campaigning for the second slot and coming up short is embarrassing, as Pawlenty remembers from his unsuccessful effort to become Sen. John McCain's running mate in 2008. McCain went with Sarah Palin.

And, potentially, no one wants to play second fiddle on a second-place ticket. If Romney falls short in his bid to make President Barack Obama a one-termer, the fresh faces in the GOP today might be tainted as losers heading into 2016 if the campaign goes badly.

Just look at Palin, the former Alaska governor. She flirted with running this year but ultimately decided against it, given her divisive reputation, lagging poll numbers and sour memories of the 2008 race.

Palin offered some advice to the nominee, whether it ends up being Romney or someone else:

"Don't necessarily play it safe and do just what the GOP establishment expects them to do," she told Fox News Channel, where she is a paid contributor. "It doesn't matter if that person has national level experience or not, they're going to get clobbered by the lame-stream media who does not like the conservative message."