New poll results on the Senate race today from Public Policy Polling show Pat Toomey opening up a tiny bit more of a lead on Joe Sestak. But it's still "somewhat of a low point" for the Demorat, they say.

(It's quite a day for polls, ain't it? Rasmussen is promising another Senate poll this afternoon.)

From PPP:

With Joe Sestak's victory in the Democratic primary and the poll bump that came with it now three months in the rear view mirror, Pat Toomey has taken a 45-36 lead in the Pennsylvania Senate race. That's a big change from the tie PPP saw in a June survey of the race but pretty similar to the solid Toomey lead our April survey showed.

Toomey's winning for the same reasons most Republican candidates across the country are doing well in key races right now:

-He has a 50-23 lead with independent voters.

-He's benefiting from a much more unified party, as he leads 74-9 with Republicans while Sestak is currently up only 64-15 with Democrats.

The key is the big guy in the White House, who seems especially unpopular in Pa:

The biggest key to the race is probably Obama's considerably fallen popularity. His approval rating stands at only 40% with 55% of voters disapproving of him, one of the biggest declines from 2008 performance we've seen for him anywhere in the country. Part of Obama's low numbers is a reflection of the Republican trending voter pool in the state this year, but there are also more people who voted for Obama but disapprove of him now in Pennsylvania than there are most places.

And one final point from the pollsters:

This may represent somewhat of a low point for Sestak. The undecided voters lean Democratic (they voted 52-36 for Obama) and it's hard to imagine the level of Democratic interest in the election going anywhere but up. But for now Toomey's in a pretty good position.

Full results here. 585 likely Pa voters surveyed Aug. 12-16 with 4.1% MoE.