Pennsylvania Sen. Arlen Specter (R) finds himself down 21 points to former Rep. Pat Toomey in a potential 2010 Republican primary, according to a new Rasmussen poll. Specter now has a 42%/55% favorability rating, while Toomey enjoys a 66%/19% rating.

Toomey 51
Specter 30
Someone else 9
Und 10

Toomey lost to Specter by a slim margin in the 2004 Senate primary, but in an on-camera interview with Pittsburgh Tribune-Review reporter Salena Zito, Toomey said things are different this time.

"It's a very different race," Toomey said. "I think the press has figured out that this time the outcome is going to be different."

"Let me assure you, I wasn't waiting around to do this. I had no intention of running again," he said. "And then all of a sudden I saw our federal government doing things that I never thought was possible."