A new poll shows that registered voters by a small margin think Mitt Romney will do a better job with Medicare, but the same poll shows opposition to Ryan's plan for the program. Meanwhile polls in Florida and North Carolina show how the race is shaping up in convention states, and Michigan is race is once again tight. Here's our guide to today's polls and why they matter. 

Findings: In a new poll, 45 percent of registered voters think Romney would do a better job on Medicare than Obama, while 42 percent think the reverse. 
Pollster: Washington Post/ABC News
Methodology: Telephone interviews with 1,002 adults, including 857 registered voters, with margin of error of +/-4 percentage points for both the full sample and the sample of registered voters. 
Why it matters: Though Talking Points Memo's Tom Kludt notes that "it isn't a massive advantage," he adds: "Medicare was supposed to be a problematic front for Romney following the selection of Rep. Paul Ryan (R-Wis.) as his running mate earlier this month." 
Caveat: The Washington Post's Ezra Klein points out that in the poll "people like Paul Ryan’s budget…" adding "…Until they learn more about it." According to the poll 64 percent oppose Ryan's Medicare plan compared to 31 percent who support it, but 47 percent like his budget plan given what they know compared to 44 percent who oppose it. 


Findings: Obama and Biden lead among likely voters in Florida 50 percent to 46 percent, whereas in North Carolina Romney and Ryan lead 48 percent to 47 percent. 
Pollster: CNN/Time Convention Floor Pass
Methodology: Telephone interviews with 776 likely voters in Florida and 766 in North Carolina with a margin of error of 3.5 percentage points for each sample. 
Why it matters: These states are in the national eye as Tampa hosts the Republican National Convention and Charlotte is set to host the Democratic. That said, Obama-Biden poll stronger in the RNC state and the race is nearly tied in the DNC state. We mentioned on Friday the significance of using likely voters in CNN's national poll, and Kludt explains that "Monday’s polls illustrate a source of concern for the Obama campaign: a drop-off in support from registered voters to likely voters. Among registered voters, Obama and Biden lead by 9 points in Florida and by 2 points in North Carolina." 
Caveat: TPM's PollTracker Average shows a 1.1 point race in Florida with Obama leading. 


Findings: Obama and Romney are tied in Michigan with 47 percent each.
Pollster: Mitchell Research & Communications, Inc.
Methodology: Automated survey of 1,277 likely voters August 23 with a margin of error of +/-2.74 percent "at the 95% level of confidence." 
Why it matters: This is a change for the state, where just 10 days ago Obama led by five points. According to Steve Mitchell from the poll: "This is a race for the independents. Ten days ago Obama had their support, now Romney does. The big change in this poll is the large shift in men voters to Romney that offsets his losing margin with women. The gender gap has become a two-way street." On Friday, after the poll was taken, Romney made a birther reference in a rally in the state. 
Caveat: Kludt points out that when the poll asked voters about the entire ticket — not just the two presidential candidates — Romney and Ryan led Obama and Biden 46 percent to 45 percent. Also, Mitchell admits: "The main argument that Obama supporters will make against the accuracy of this poll is that Obama is only getting 73% of the vote from African-Americans." He challenges: "That fact, however, does not make this poll inaccurate. I agree that eventually, at least 90% of African-Americans will vote for Obama.  Obama’s problem now is that he is running behind the party vote among blacks."