PORTLAND, Ore. -- Republicans go after Barack Obama in their political advertising, but GOP Senator Gordon Smith aligns himself with the Democratic presidential candidate in a new ad, citing work they both did to improve fuel efficiency standards.

File Photo

U.S. Sen. Gordon Smith, R-Ore.

It may be the first time in this election cycle that a GOP Senate candidate had aligned with Obama.

The ad, responding to attempts to tie Smith to high gas prices, credits Obama with saying that "Gordon Smith led the fight for better gas mileage and a cleaner environment."

Democrats take issue with that.

Matthew Miller, a spokesman for the Democratic Senatorial Campaign Committee, said the two worked together on the 2006 fuel efficiency bill, but Obama never called Smith a leader.

Obama's campaign said Obama appreciates that his record of bipartisan achievement is respected by both parties.

But Obama is backing Democrat Jeff Merkley in the Oregon Senate race.

Smith is trying to keep his seat in a state that's been tilting toward Democrats. Polls still show him leading Merkley.