(Yakima, WA)  --  Democratic presidential candidate Bernie Sanders will return to Washington tomorrow, for a campaign rally in Yakima.  He's slated to be at the Yakima Valley SunDome for the four p.m. event.  On Friday, the Vermont senator will hold another four p.m. rally at Safeco Field in Seattle, a day ahead of the Democratic caucuses in Washington.  Sanders visited Washington last Sunday, making campaign appearances in Vancouver, Seattle, and Spokane.