With two-thirds of the ballots counted in Washington state, it appears very likely that Democratic incumbent Patty Murray is headed back to the U.S. senate for a forth term.

Murray now leads Republican challenger Dino Rossi by more than 27,000 votes - up from 14,000 on election night. Overnight, Rossi's numbers fell in 18 of 22 counties that reported new totals.

While Rossi won all of rural, eastern Washington, Murray is winning the more populated coast.Analysts say Rossi needed to get 40% of the vote in King County, but he's only got 37% He also needed to win both the Seattle suburbs -- Pierce and Snohomish County..and he's currently only ahead by a tiny margin in Pierce.

Rossi had hoped late voters would break Republican but that does not appear to be happening. His campaign remains optimistic and says the race is still too close to call and that there are still hundreds of thousands of ballots which need to be counted.

New numbers from predominantly Democratic King County will be released at 7:30ET.

The bottomline is, if margins hold - Washington state's Patty Murray - the nation's fourth most powerful Democrat- stays in Washington, DC.