Colorado, a back-up for Obama, has the president in a small lead for the most part, a CNN/ORC International Poll has Obama up by three, and Mourdock drops (though not according to him) in Indiana. Here's our guide to today's polls and why they matter.

Findings: A Colorado poll from Public Policy Polling for the League of Conservation Voters finds Obama up by four, but the Denver Post has Obama up by two points. In a Reuters tracking poll, he and Romney are tied in the state.
Pollster: Public Policy Polling, Denver Post/SurveyUSA, Reuters/Ipsos
Methodology: For PPP: Poll of 825 likely voters October 31 through November 1. For Denver Post: Poll of 695 voters likely October 28 through 31. For Reuters/Ipsos: Online tracking.
Why it matters: Colorado's important for Obama, according to Nate Silver. If he loses the key state of Ohio, but keeps others, "the tipping-point would then become Colorado." Here it looks tight, but Obama's not in the red.
Caveat: While a poll out from CNN yesterday had Obama up by two, the right-leaning Rasmussen saw Romney with a three-point lead. PPP is Democratic-leaning.


Findings: Obama's up by three in Ohio in a CNN/ORC International poll.
Pollster: CNN/ORC International
Methodology: Poll of 796 likely voters October 30 through November 1.
Why it matters: It's Ohio. Of course it matters. It's the state that's needed to win or life is going to become really hard. This poll reaffirms a consensus that Obama is up by a small margin.
Caveat: There are of course the "known unknowns," or the argument from people like The New York Times' David Brooks, MSNBC's Joe Scarborough, and The Daily Caller's Matt Lewis, that "the race feels closer than the polls say," which our Elspeth Reeve has mentioned. Right-leaning Rasmussen, for instance, has the race tied, and if you're looking at it from a Republican perspective, Romney's internal polling is telling a different story.


Findings: A bipartisan poll from Indiana has Democrat Joe Donnelly leading Republican Richard Mourdock by 11 points. Rasmussen puts Donnelly up by only three.
Pollster: Howey/DePauw Poll, Rasmussen
Methodology: For Howey: Poll of 800 likely voters October 28 through 30. For Rasmussen: Automated poll of 600 likely voters November 1.
Why it matters: When we previously looked at this race following the Mourdock incident, polling was from partisan pollsters. Here we have a bipartisan look from Howey/DePauw, and it appears that Mourdock has taken a big slip since he commented that pregnancy from rape was "a gift from God." Even in the right-leaning Rasmussen, Mourdock is down.
Caveat: Mourdock released internal polling that shows him leading by two percentage points.