Mitt Romney is polling just behind President Obama in Florida, a state he needs to win to get enough electoral votes unseat the president. While he's behind Obama on a lot of issues, Romney has an advantage on the economy. Here's our guide to today's polls and why they matter.

Findings: Obama is leading Romney just barely in Florida, by 45 percent to 43 percent. If popular freshman Florida Sen. Marco Rubio is Romney's running mate, Obama is still ahead, but by slightly less, with 45 percent to the Republicans' 44 percent.
PollsterFox News
Methodology: Survey of 757 registered voters from April 15 to April 17.
Why it matters: Romney probably needs to win Florida to get to 270 electoral votes, but every poll released since February has shown Obama ahead in the state.
CaveatPublic Policy Polling finds that adding Rubio to the ticket actually hurts Romney nationally.

Findings: The gap between Obama and Romney has narrowed. Polls differ in how much -- NBC/ Wall Street Journal says Obama's ahead by 6 percentage points, while CBS/ New York Times finds them tied, and Gallup finds Romney up by 5 points. But the gap is smaller.
Pollster: NBC/ Wall Street Journal; CBS/ New York Times; Gallup
Methodology: All these polls are of registered voters -- not likely voters -- the earliest survey beginning April 13 and the latest ending April 18.
Why it matters: While Republicans are despairing that Romney is doomed, the polls show that's not quite the case. Even Romney-backer Sen. John McCain told Fox News Thursday night, "Right now, let's have some straight talk, we're running behind, okay. I think it's about five or six points." McCain, though, is one of the more optimistic Republicans: "It's always better to run from behind.... so let's assume that we're behind, and that is we've got to hone our message, and we can do that, and I'm convinced that the speeches that Mitt Romney's been making lately are outlining, laying out that agenda for the future."
Caveat: Even as the polls narrow, Obama has advantages like money, organization, and incumbency, The Hill's Christian Heinze points out.

Findings: Romney's message that he's the guy to fix the economy seems to be working: While Obama beats him on a lot of issues, 40 percent of voters think Romney has better ideas for the economy, while 34 percent think that about Obama. And while 75 percent of voters say they'd vote for the guy who will fight for "fairness" -- an Obama talking point -- only 45 percent like the pitch that there's a widening gap between the rich and everyone else. 
Pollster: NBC/ Wall Street Journal
Methodology: Survey of 1,000 registered votes, 250 of them on cell phones, from April 13 to April 17.
Why it matters: While the economy has been improving the last few months, there's increasing fear in the U.S. and Europe that momentum will stall. IMF chief Christine Lagarde, for example, said Thursday that while a "light recovery [is] blowing in a spring wind," there are "dark clouds on the horizon," The New York Times reports. If the economy gets worse, voters will be more likely to look for someone who promises to make it better. Romney has said he doesn't want to talk about distractions -- like the mommy wars, the doggie wars, whatever -- that keep him from talking about the economy. That's smart! Why doesn't his staff agree?
Caveat: The poll still finds Obama beating Romney among true swing voters. And a Gallup poll released Friday finds 50 percent of Americans have a "great deal" or "fair amount" of confidence Obama will do the right thing for the economy, while 42 percent think that about Romney.