WASHINGTON -- With two weeks to go, the Washington state U.S. Senate race is a virtual dead heat, with Democratic Sen. Patty Murray holding a one-point lead among probable voters of 48-47 percent over Republican challenger Dino Rossi, according to a McClatchy-Marist poll released Tuesday.
That lead is well within the poll's margin of error, meaning neither candidate has a clear advantage.
The outcome of the race could determine whether Republicans pick up the 10 seats they need to regain control of the Senate.
"This is indeed a cliffhanger, any way you carve up the numbers," said Lee Miringoff, the director of the Marist Institute for Public Opinion in Poughkeepsie, N.Y., which conducted the survey. "The road to a Republican majority in the Senate could go through Washington state."
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Other recent polls have shown a volatile race, with Rossi having a slim lead in some and Murray up by 6 to 8 points in others.
Murray, who ranks fourth in the Senate Democratic leadership and is a senior member of the Senate Appropriations Committee, is seeking a fourth term. Although she has had strong challengers in the past, this is by far her toughest race. Rossi, a former state legislator and a businessman, has run twice unsuccessfully for governor.
Rossi has had strong support from the GOP establishment in Washington, D.C., which was instrumental in convincing him to run. As opposed to some Democratic candidates elsewhere, Murray remains an outspoken supporter of the Obama administration's economic stimulus measure, health care overhaul and Wall Street regulation.
Among all registered voters, Murray held a larger lead, 47-42 percent, but Miringoff said likely voters who indicated they almost would certainly vote reflected a more accurate picture of the race -- a dead heat.
The phone survey included a representative sample of 834 registered state voters selected to cover each region of the state in proportion to its population. The declared margin of error was 3.5 percentage points for all voters and 4 percent for likely voters.
If the Washington race is as close as the poll shows, the outcome could take days or weeks to determine. Rossi lost the race for governor in 2004 by 133 votes. It took 58 days to determine a winner, then a court case challenging the outcome stretched into June of the following year.
Washington has a history of close races. Democratic Sen. Maria Cantwell won her first race for the Senate by 2,229 votes in another contest that took weeks to resolve.
"It does remind you of Florida in 2000 if it happens," Miringoff said of the presidential campaign between Al Gore and George W. Bush, which ultimately was resolved by a 5-4 Supreme Court decision.
Forty-seven percent of Washington state voters told the pollster they were independents, 32 percent said they were Democrats and 21 percent said Republicans.
Tuesday's poll found Democrats lined up overwhelmingly behind Murray, Republicans overwhelmingly behind Rossi and the crucial block of independent voters breaking for Rossi by 57-36 percent.
There was a major gender gap. Women supported Murray 55-41 percent, while men supported Rossi 53-41 percent.
Forty-nine percent of likely voters have favorable impressions of Murray and 44 percent unfavorable views, the poll found. Forty-six percent of voters have favorable impressions of Rossi and 46 percent unfavorable ones.
Rossi was running strong, 59-35 percent, in conservative Eastern Washington.