UPDATED AT 8:35 a.m. with comments from Barreto.

WASHINGTON -- Sen. Patty Murray's reelection wasn't nearly the squeaker that many polls had predicted. So who came closest to calling Murray's 4.4-point margin of victory over Republican Dino Rossi?

University of Washington pollster Matt Barreto says he did.

Barreto, director of The Washington Poll, said his October 28 survey proved most accurate among the 9 polls released in the final week before election day. Barreto's poll showed Murray edging out Rossi by 49 to 45 among registered voters. As of Tuesday, Murray hasgarnered 1,273,790, or 52.2 percent, of the votes; Rossi won 1,165,852, or 47.8 percent. Final election results are scheduled to be certified next week.

Barreto's 0.4 error was narrower than the 0.6 margin from the October 30 YouGov poll, which found Murray up by 5 points among registered voters. YouGov, however, came closer to the actual results by showing Murray leading by 3 points among people deemed most likely to vote, compared to 6 points in Barreto's poll.

The worst -- and the most surprising -- performance was by Public Policy Polling (PPP), which predicted a 2-point Rossi victory. That was despite the fact that PPP's poll had the biggest sample size and was conducted closest to Nov. 2 -- not to mention that it's a Democratic polling firm.

The second-least accurate poll was conducted just a day before Barreto's by Rasmussen. The firm, which has come under fire in some quarters this year for a pronounced Republican tilt, called for Rossi eking out a 48-47 win. Barreto immediately dismissed Rasmussen's forecast at the time, calling it "a known outlier."

On Tuesday, Barreto offered a couple of theories about his rivals'performance. For instance, both Rasmussen and PPP use robocalls. That could underrepresent respondents who are older or less educated, people who tend to prefer to talk to a live caller. It also misses younger voters who use mobile phones exclusively, as cell phones mustbe hand dialed.

But most crucially, Barreto contends that other pollsters simply lack familarity with Washington to produce good polls. Barreto has repeatedly boasted that in 2008, The Washington Poll showed Gov. Christine Gregoire ahead of Rossi by 6 points. She won with 6.5 points.

"The headline here is, 'For second straight election, Washington Poll is most accurate in the state," Barreto crowed.