Almost immediately after Dino Rossi‘s entrance into the U.S. Senate race, the Cook Political Report declared Sen. Patty Murray‘s seat is now in play.

The national newsletter published by political analyst Charlie Cook rates the race as a “toss up,” a change from its previous status as “solid Democrat.”

That makes 11 competitive races for Senate seats now held by Democrats, the report says. Republicans need 10 seats to gain control of the Senate, if they hold another eight GOP seats that, in the Cook Political Report’s view, are in play this year.