Two new surveys show a tight race for the important swing state of Ohio, with one showing a razor-thin Obama lead and the other finding a tie in the state.

One new poll, conducted by the Democratic firm Public Policy Polling, finds Obama leading Romney, 48 percent to 45 percent, within the margin of error of 3.2 percentage points.

Democratic Sen. Sherrod Brown holds a more solid lead in the state's senate race, 47 percent to 37 percent over Republican Josh Mandel.

The other survey, released Tuesday by Rasmussen Reports, finds Obama and Romney tied at 45 percent.

Most other recent polls have found Obama holding at least a small lead in the state, and the current Huffpost Pollster estimate is that Obama leads the race, 47.4 percent to 44.3 percent.

Both the Rasmussen and PPP surveys were conducted using automated, recorded-voice polling technology. The PPP survey was conducted Aug. 9-12 among 961 likely voters. The Rasmussen Reports survey was conducted Aug 13 among 500 likely voters, and has a margin of error of 4.5 percentage points.

The polls show both Obama and Romney struggling to impress Ohio voters. More voters disapproved than approved of Obama's job performance in each poll, by a 51 percent-to-46 percent margin in PPP's survey and 51 percent to 48 percent in the Rasmussen poll. Similarly, the surveys found a majority of Ohio voters have an unfavorable opinion of Romney, by a narrow 50 percent-to-49 percent margin in the Rasmussen poll and a larger, 52 percent-to-41 percent margin in PPP.

Respondents to the Rasmussen poll gave strong marks to Romney's vice presidential pick, Paul Ryan: 51 percent of those surveyed had a favorable opinion of Ryan and 39 percent had an unfavorable opinion (respondents to the poll were told that Ryan was Romney's vice presidential candidate before being asked to rank him). Respondents were more divided on Ryan's readiness to be president: 38 percent said he was, while 41 percent said he was not. However, by a 49 percent-to-22 percent plurality, Rasmussen responents said Romney's selection of Ryan was the right choice.

The PPP survey, which went into the field last Thursday before news of Romney's selection of Ryan as his running mate leaked, found more mediocre numbers for Ryan: 34 percent of those surveyed said they had a favorable opinion of Ryan, 33 percent an unfavorable opinion; 33 percent were undecided.

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