A bill to change the way Virginia awards its electoral college votes, and perhaps boost Republicans’ prospects in a state that went for Barack Obama in the last two presidential elections, appears to be headed for defeat.

Gov. Robert F. McDonnell (R) and two GOP senators on a crucial committee came out against the measure Friday, apparently dooming its chances of getting to the Senate floor.

Sen. Jill Holtzman Vogel (R-Fauquier) said in an interview with The Washington Post Friday that she would not support the bill. “I think it’s not a good policy decision right now,” Vogel said.

Sen. Ralph Smith (R-Roanoke) told The Roanoke Times that he also opposes it.

McDonnell spokesman Tucker Martin wrote in an e-mail: “He believes Virginia’s existing system works just fine as it is. He does not believe there is any need for a change.”

In Virginia, as in most states, the presidential candidate who wins the popular vote receives all of that state’s electoral votes. A bill proposed Sen. Charles W. Carrico Sr. (R-Grayson County), would instead apportion electoral votes by congressional district.