WASHINGTON – Sen. Pat Toomey (R., Pa.) leads potential Democratic challenger Joe Sestak by 10 percentage points in a new Quinnipiac Poll examining what seems on track to be a re-match of their 2010 Senate race.

UPDATED: The poll, out Tuesday, found that Toomey has support from 45 percent of Pennsylvania voters against 35 percent for Sestak in a head-to-head match-up. Toomey is seeking re-election next year and so far Sestak is the only Democrat to show serious interest in challenging him -- though former Congressman Chris Carney has also said he may run.

Sestak, a former Delaware County Congressman, narrowly lost to Toomey in 2010.

The poll, of course, comes nearly two years before Election Day and before either man launches a full-fledged campaign. Much can happen before then to change voters' opinions: the 2016 presidential race will surely figure into campaign, both national parties are expected to flood Pennsylvania with ads for what is expected to be a hotly-contested Senate campaign, and other Democrats could still enter the race to challenge Sestak, though as time goes on that possibility seems less and less likely.

What the poll does demonstrate, though, is that Toomey retains strong support among Republicans despite several notable moves toward the middle ground (and, theoretically, critical swing voters) since his election in 2010. Among Republicans, 87 percent said they'd vote for Toomey if the election were held today.

Toomey also won 48 percent of independents in the poll, compared to 25 percent for Sestak. Of course, being an incumbent helps -- Toomey is regularly in the news while Sestak is not -- but it also shows that Toomey has a significant level of support among these key voters. Sestak, or any Democratic challenger, would have to work to change their opinions of the incumbent.

Sestak would win support among 68 percent of Democrats, showing that he has work to do among some within his party, but also showing a path for gaining ground. He could have help from the presidential contest, which typically rallies Pennsylvania Democrats to the polls.

Toomey's personal favorability rating stands at 37 percent favorable to 21 percent unfavorable. His job approval was slightly better: 43 percent approve of how he has done his job against 25 percent who disapprove.

Sestak was seen favorably by 23 percent of voters, against 12 percent who see him unfavorably. The majority  -- 64 percent – don't know enough about him to form an opinion, though both parties will surely be working to change that.

The poll surveyed 881 Pennsylvania voters and had a margin of error of 3.3 percentage points.

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