Portland, Ore. (AP) -- A new poll shows Barack Obama with a huge lead over Hillary Clinton in Oregon as the state heads into the final week before its primary election votes are counted.

Obama led 55 percent to 35 percent over Clinton among Oregon voters surveyed -- a lead considered nearly insurmountable.

The poll of 400 likely Democratic voters across the state has a margin of error of plus or minus 4.8 percentage points.

The fact that Obama is favored by a percentage of voters well beyond that margin of error this close to the election suggests his victory in Oregon is nearly certain.

The statewide polling was conducted May 8-10 by Davis, Hibbitts & Midghall for the Portland Tribune and KPTV.

More: Complete Election Coverage