(CNN) - It may be his home state, but a new poll indicates that Rick Santorum is not on top in Pennsylvania in the fight for the GOP presidential nomination.

And the Quinnipiac University survey of Keystone state voters released Wednesday also indicates that President Barack Obama's re-election numbers are on the rise in the crucial battleground state.

According to the poll, former Massachusetts Gov. Mitt Romney leads the Republican field at 21 percent, followed by Santorum at 16 percent and former Alaska Gov. Sarah Palin at 11 percent. No one else was in double digits and 17 percent are undecided.