PHILADELPHIA — Campaign supporters disappointed by Pennsylvania Sen. Arlen Specter's decision to switch parties can have their donations refunded if they choose, the senator said Friday.

Specter, making his first appearance in the state since becoming a Democrat earlier this week, said he was unaware if anyone had asked for refunds. But he noted he has "already had the checks cut" to return contributions Senate colleagues made to his political action committee.

Specter said he would not ask fellow senators to return donations that his committee made to their campaigns.

"They fit in my tent. I just don't fit in theirs," he said.

The senator has been a Republican since 1965. His moderate views have often put him at odds with the party and he said polling data indicated "bleak" prospects for re-election in 2010 if he remained with the GOP.