Washington (CNN) - Two well respected non-partisan political handicappers say Republican Dino Rossi's entrance into this year's Senate battle in Washington state is putting the Democratic-held seat into play.
Rossi officially announced his bid Wednesday.
Thursday, the Cook Political Report moved its rating of the contest from "solid Democrat" to "toss up" and the Rothenberg Political Report changed its classification from "safe" for Sen. Patty Murray, the Democratic incumbent, to a "narrow advantage for the Democrats."
Rossi, currently a commercial real estate investor, is arguably the best known Republican in Washington state, thanks to his two bids for governor. In an election that went into overtime, Rossi lost to Democrat Christine Gregoire by just a handful of votes six years ago. He was again defeated in a 2008 rematch by a wider margin.
Polls of Washington state voters conducted earlier this year suggest that Rossi, a former state senator, could be competitive with the three-term Murray, the so-called Senate "soccer mom" whose approval rating is hovering around 50 percent among Washington state voters. But Murray is sitting on a formidable $6 million campaign war chest, according to disclosures filed with the Federal Elections Commission at the end of March, and handily won her reelection bids in 1998 and 2004.
Rossi's announcement came just days after Alaska Gov. Sarah Palin endorsed another Republican running for the seat, Tea Party favorite and formal NFL player Clint Didier. Didier himself has attacked Rossi as a firmly entrenched member of the Republican establishment. Washington state holds its primary on August 17.
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