Without their votes, Mr. Obama and Democratic leaders don't have a majority in the Senate, let alone the 60 votes needed to break Republican filibusters. That gives Mr. Bayh and his group an opportunity to assert themselves.
"We really do need to change business as usual," Mr. Bayh said in an interview Monday. "People want results."
The group's biggest immediate impact may be on the president's budget, which is now working its way through Capitol Hill. The group has met privately with Senate Budget Committee Chairman Kent Conrad (D., N.D.), who plans to pare back Mr. Obama's spending blueprint. The moderates will press for more cuts when the full House and Senate consider the budget next week.