HARRISBURG — Pennsylvania's Democratic chairman said Thursday the party would be better off if U.S. Rep. Joe Sestak were to abandon his bid for Sen. Arlen Specter's seat and instead seek a third term in the House.

T.J. Rooney was reacting Thursday to Republican Scott Brown's Senate victory in heavily Democratic Massachusetts on Tuesday and polling that suggests Republican and former Rep. Pat Toomey might be pulling ahead in a hypothetical November matchup against the fifth-term Specter, who defected from the GOP last year.

Rooney said a Sestak withdrawal would allow Specter to focus more on the general-election campaign, while Sestak, a retired Navy vice admiral, could lock in his seat representing the 7th District in suburban Philadelphia for two more years — saving the party money in an important election year.

Sestak's campaign responded it will stay the course.

Spokesman Jonathon Dworkin portrayed Specter as a party-switcher desperate to keep his job and said Sestak expects to be the party's standard-bearer in November.

"You see how well Joe Sestak — relatively unknown — does against Toomey compared to Specter, who has spent a generation in Washington," Dworkin said.

To qualify for the May 18 primary ballot, congressional candidates have until March 9 to file papers. One Democratic candidate, state Rep. Bryan Lentz, is already campaigning for Sestak's seat and Pat Meehan, the former U.S. Attorney for the Eastern District of Pennsylvania, is seeking the Republican nomination.