OLYMPIA, Wash. (AP) - Washington Governor Chris Gregoire's big biodiesel campaign bus has Oregon plates.

State Republican Chairman Luke Esser brought it to reporters' attention on Thursday. He says it's a symbolic reminder that Democrat Gregoire is throwing small businesses under the bus.

Gregoire used the bus as a photogenic part of her campaign tour of 10 cities this week. The GOP is circulating photos that show Oregon plates on the big rig.

The governor's campaign spokeswoman says the bus was rented from a Washington company.