Democratic Sen. Patty Murray and Republican challenger Dino Rossi are roaring across Washington state in the final weekend of their closely watched contest.
Both candidates are hosting a string of get-out-the-vote rallies, urging supporters to mark their mail-in ballots by Tuesday's deadline.
Republicans need 10 seats to gain control of the Senate, and the competitive Washington Senate race could be key to the outcome.
The state's election actually began two weeks ago, after county officials finished sending out ballots to voters' homes. Almost everyone in the state votes by mail.
Ballots have to be postmarked by Election Day. That means it can take several days for all the votes to be counted.
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