President Obama's job approval rating is inching upwards -- and while he loses to a generic Republican, voters are still skeptical of the current Republican lineup. Here's our guide to today's polls and why they matter.

Findings: 46 percent of Americans say they approve of how President Obama's doing his job. 
Pollster: Gallup
Methodology:  Telephone interviews with about 1,500 national adults.
Why it matters: On Monday, Obama was above water for the first time in a long time -- 47 percent approving to 45 disapproving. Was it a blip of holiday cheer? Maybe. On Tuesday, Gallup's tracking poll dropped his approval rating down a point and the disapproval rating up three. Still, Obama's recovered a lot from where he was in mid-October, when he hit his all-time low of a 38 percent approval rating. He was at 42 percent just 10 days ago, Politico notes. The fight with House Republicans over the payroll tax might have had something to do with it -- 46 percent of the public backed Obama on the issue, while 41 percent trusted Republicans, a Washington Post/ ABC News poll found. Pew Research Center found 57 percent of Americans think the worst thing about the American tax system was that "wealthy people don't pay [their] fair share."
Caveat: It's not clear yet whether Monday's showing was a blip or the start of a trend.
 
Findings: 39 percent of Republican voters back Mitt Romney in the Republican primary.
Pollster: Boston Globe/ University of New Hampshire Survey Center.
Methodology:  Live telephone survey of 543 likely Republican voters called bwteeen December 12 and December 19.
Why it matters: Romney is down 3 percentage points but still far ahead of Newt Gingrich and Ron Paul, who have 17 percent. Jon Huntsman is running a one-state campaign in New Hampshire, and just two weeks before voting, he's in fourth place with 11 percent. The New York Times' Nate Silver's election forecast now gives Romney a 74 percent chance of winning in New Hampshire.
Caveat: Silver points out that Romney's poll numbers "are not those of a traditional fronrunner." It's widely expected that he'll win, yet his poll numbers haven't improved much. "This disconnect between expectations and performance is potentially quite dangerous to Mr. Romney," Silver writes. He says there are plausible but not necessarily likely scenarios where Romney gets as little as 8 percent in Iowa. "Even a third-place finish in Iowa, much less something worse, might now be viewed as disappointing for Mr. Romney, increasing the risk of either a loss in New Hampshire or a close call that made Mr. Romney vulnerable heading into South Carolina and Florida."
 
Findings:  Obama trails a generic Republican in the general election 44 percent to 45 percent.
Pollster: Rasmussen
Methodology:  3,500 likely voters phoned between December 19 and December 22.
Why it matters: The same pollster finds Gingrich trailing Obama 37 percent to 47 percent. Just like the Weekly Standard's Bill Kristol, it looks like voters are still hoping for a better Republican candidate to replace Obama.
Caveat: Rasmussen leans right.