PHILADELPHIA — Rep. Joe Sestak ventured Tuesday morning to the Democratic stronghold of West Mount Airy, greeting primary voters on their way to the polls as he looked to upend Sen. Arlen Specter in their neck-and-neck fight for their party’s Senate nomination.

This historic northwest Philadelphia neighborhood is the kind of region that tends to vote strictly Democratic, and Specter’s performance here could prove crucial to the former Republican’s ability to hold off Sestak, who represents a House seat in the nearby suburbs. Sestak expressed confidence that victory was at hand and credited what he said has been a negative reaction to Specter’s party switch last year as the reason for his optimism.

“I respect Arlen Specter, but his time has come and gone,” Sestak told reporters outside the Summit Presbyterian Church, where voter turnout was reported to be light.

The church location, which is the polling place for two voter divisions, is heavily Democratic, with a combined registration count of approximately 1,300 Democrats, to just 70 Republicans.

David Meketon, who ended up voting for Sestak after much soul-searching, is the kind of Democratic voter who could spell trouble for Specter. The 53-year-old educator said the decision was tough, but he ultimately could not look past the Senator’s party switch.

“It was impossible. I changed my mind five or six times,” Meketon said. “Sestak —his character and his values better reflect my values than do Arlen’s.”

Meanwhile, Sestak indirectly vowed to support Specter over former Rep. Pat Toomey (R) in the general election if he loses Tuesday.

“At the end of the day, I will do anything to beat Pat Toomey,” Sestak said.