WASHINGTON – Joe Sestak just finished walking 422-miles across Pennsylvania -- and slipped three points further behind Sen. Pat Toomey (R., Pa.), according to a Quinnipiac University poll out Monday.

Toomey (R., Pa.) holds a 13 point edge over Sestak, a Democrat, in a potential 2016 match up, according to the survey. It found that 48 percent of voters would back Toomey in a head-to-head match up, against 35 percent for Sestak.

A Q Poll in February -- before Sestak's walk began -- gave Toomey a 10-point lead.

"It's an uphill fight for Joe Sestak," said Tim Malloy, the poll's assistant director.

Toomey narrowly beat Sestak, a former Delaware County congressman, in 2010, but voters in this poll give the incumbent positive marks while few seem to remember Sestak, despite his recently completed trek.

Of course, polls this early give a hint of the starting point, but there is a lot that will still happen between now and Election Day 2016.

The new poll surveyed 1,036 Pennsylvania voters with a margin of error of 3 percent.

Toomey's job approval rating stood at 49 - 24, and 44 percent of voters see him favorably, compared to 23 percent who view him unfavorably. Sestak's favorability was at 24-14, but 61 percent didn't know enough about him to form an opinion.

That means he has room to grow, but a lot more work to do. So far, Sestak is the only Democrat to jump into the race, though others are said to be mulling it.

Montgomery County Commissioner Josh Shapiro, Philadelphia State Sen. Vincent Hughes and former Congressman Chris Carney have all said they are considering running. Allentown mayor Ed Pawlowski told the Pittsburgh Post-Gazette he is also considering a run.

Despite Toomey's strength, Democrats hope that a strong presidential candidate atop the 2016 ballot will give their party a boost down the ticket, and help them topple the incumbent. Another Quinnipiac Poll last week, though, cast some doubt on that theory, showing Hillary Clinton's numbers slipping in the commonwealth.

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