Romney's take on the 47 percent is making him less appealing to some voters, the tracking polls are tight, more Wisconsin polls show the state leaning towards Obama, and a poll shows Scott Brown up in what would be a switcheroo for the Massachusetts Senate race. Here's our guide to today's polls and why they matter.

Findings: A Reuters/Ipsos poll found that 43 percent of registered voters viewed Romney less favorably after seeing his 47 percent comments, and 59 percent said they thought he "unfairly dismissed almost half of Americans as victims." A lesser amount, 36 percent of voters in a USA Today/Gallup poll said the comments made them less likely to vote for him, while 29 percent of independents said it made them less likely, 15 percent said it made them more likely, and 53 percent said it made no difference.
Pollster: Reuters/Ipsos, USA Today/Gallup
Methodology: For Reuters: Survey of 869 registered voters September 15 to 19 with a "credibility interval" of 3.8 points. For Gallup: daily tracking telephone interviews with 885 registered voters September 18.
Why it matters: The 47 percent comments created media hubbub since they were released, and these polls indicate that at least some voters have indeed reacted negatively. That said, Gallup notes: "A substantial majority of Americans have already made up their minds about their vote choice, so it is likely that many of those who claim to be 'more likely' or 'less likely' to vote for Romney are, in essence, indicating that the comments reinforced their pre-existing vote choice." And, for Reuters, Ipsos pollster Julia Clark explains: "This type of issue, a gaffe or an indiscreet remark by a candidate, has an effect on a candidate's image, but it is not the kind of thing that decides how people vote on Election Day."
Caveat: Both polls caution that negative reaction right now might not have long term impact.


Findings: Rasmussen's tracking poll has Obama up by two points, whereas Gallup's has the race tied.
Pollster: Rasmussen, Gallup
Methodology: For Rasmussen: Three day rolling average of 500 likely voters per night with a +/-3 percent margin of error. For Gallup: Seven day rolling average of 3,050 registered voters with a margin of error of +/-2 percent.
Why it matters: In a post this morning Nate Silver wrote, "The most compelling case that Mr. Obama’s bounce is diminishing is from the Gallup and Rasmussen Reports tracking polls, both of which were unchanged on Wednesday, but which have reverted sharply from their post-convention peaks and are now at their preconvention levels instead."
Caveat: While it should be noted that the two polls have different methodologies, Silver also adds: "just as a thought experiment: if you exclude the Gallup and Rasmussen Reports tracking polls, it isn’t clear at all that Mr. Obama’s bounce is decaying."


Findings: Rasmussen has Obama up by three points in Wisconsin, while Public Policy Polling has him up by seven.
Pollster: Rasmussen, PPP
Methodology: For Rasmussen: automated poll of 500 likely Wisconsin voters September 17 with a margin of error of +/-4.5 percent. For PPP: automated poll of 842 likely Wisconsin voters September 18 and 19 with a margin of error of +/-3.4 percent.
Why it matters: Yesterday was a nutty day in the polls for Wisconsin, Paul Ryan's home state, with a Marquette University Law School poll showing Obama leading by 14 points. As Silver explained: "There is no plausible universe in which Mr. Obama wins Wisconsin by 14 points but loses New Hampshire by three." That said, these polls do put the race in Obama's hands. As Tom Kludt at Talking Points Memo points out in regards to the PPP poll, "It’s also a big jump since last week, when PPP showed Obama clinging to a 1-point lead there."
Caveat: PPP leans left. Rasmussen leans right.


Findings: A new poll shows Scott Brown four points up against Elizabeth Warren in Massachusetts among likely voters.
Pollster: University of Massachusetts Lowell/Boston Herald
Methodology: Telephone interviews with 497 likely voters September 13 through 17 with a margin of error of +/-5.5 percentage points.
Why it matters: Earlier this week Warren was apparently riding a convention high to a lead in the state, but this poll shows her competitor back in front.
Caveat: Mark Blumenthal at the Huffington Post explains: "Relatively small sample sizes likely contribute to the variation. All but one of the new surveys sampled from 400 to 600 likely voters, for reported margins of error ranging from +/- 4 percent to +/- 5 percent."