The primary pool for the Republican presidential nomination is beginning to form. But with the value of being considered a potential presidential candidate (lots of cable news invites, political reporters hanging on your every word, general political flattery) often outweighing the headaches of actually running (message control, filing papers with the Federal Election Commission, avoiding gaffes, embarrassing single-digit poll results), it's tough to tell who's serious and who's not.

We sifted through today's speculation and tea-leaf-reading and tried our best to ascertain the intentions of the most bandied-about names:

Newt Gingrich: This past Monday, Newt was a mere four steps away from announcing his candidacy, but now is beginning to waffle. And his time out of the political spotlight hasn't reflected well on his reputation: an unscientific website poll of conservative-leaning NRO readers found that 67% think his circumspect announcement is just a bid to sell more books. Still, by signaling his intentions to run, he lost his Fox News pundit gig, which is probably a better way to sell books than running for president. Is he running? Yes, but he may reconsider.

Rick Santorum: He's hitting the campaign trail in Iowa, South Carolina and New Hampshire already, and appeared with CNN's John King to snipe Huckabee and Palin about their still-intact Fox News contracts. He's also been one of the most vocal critics of Obama's DOMA decision and appears to be trying to outflank Huckabee as the social conservatives choice this time around. Is he running? If Fox News thinks he's serious, then so do we.

Sarah Palin: Despite being the most widely covered potential candidate, no one knows a thing about what the former reality TV star will eventually decide to do. If she decides that she'll lose all relevance if she doesn't run then she'll probably throw her hat in the ring. Otherwise look for more memoirs, TV deals, lucrative speaking gigs and spin-off brands. We can only point to Sarah Palin's penchant for self-promotion as her mitigating factor for whether or not she'll eventually decide to run. Is she running? Your guess is as good as ours. But she probably has the most to gain by keeping everyone guessing. 

Mike Huckabee: As far as press coverage goes, no GOP candidate has seen his stock fall farther than Mike Huckabee recently (see: his comments about Obama's "Kenya" upbringing, and his "Madrassa" follow-up interview). Maybe Huckabee was being too congenial to Obama to ever win in a Republican primary, if so then his recent tack to the hard-right may mean that he has decided to embrace a new strategy and run. Then again, he also really likes selling books and being a Fox News pundit. Is he running? Probably. But he's got to keep his Fox News job while Gingrich and Santorum were forced to take leaves until they make up their minds. 

Michele Bachmann:  The Minnesota Rep. has made a name for herself as the Tea Party spokesperson, delivering the counterpoint to the President's State of the Union address. Her recent interviews sound like she's actually given real thought to a bid (instead of just seriously pretending). But Bachmann still hasn't decided whether she's going to run, even though she's visited Iowa and will soon be stopping in for an event in New Hampshire. Is she running?  Probably not, but she'd like to be considered.

Mitch Daniels: Fox News really likes the Indiana Governor, but he's said he wouldn't run if the state legislature is still at an impasse over public worker collective bargaining. Still, the Washington Post reports Daniels is "keeping the door open" for a run but "has made no such plans" as of now. Is he running? Not yet.

Mitt Romney, Tim Pawlenty, Haley Barbour, Jon Huntsman, Herman CainBobby Roemer: All have either made official exploratory announcements or sent obvious signals. Are they running? Without a doubt.