Biden told regional reporters in a telephone conference that he had not spoken with Specter about his position on the bill.
"But knowing Arlen, I believe Arlen will probably have an open mind if there's a compromise offered," Biden said. "But I don't know. That's my 34-year history of dealing with him. He's an intelligent, open-minded guy and I think he would listen to alternatives."
Biden said he remains hopeful that Congress will pass the bill, saying the White House is in "constant discussion" about it with labor and business groups.
"We are working very closely with labor, we support card check," Biden said.