In Oregon, Gordon Smith has been in the Senate for a little over a decade after taking over Republican Mark Hatfield's seat when he retired in 1996.
This race wasn't expected to be hot as Smith seemed to be pulling away when polls were taken in August, but Jeff Merkley closed the gap in September and two of three October polls show him with a small but significant lead (the third poll has him tied.)
It's an interesting race as Oregon is a quite polarized electorate, with liberal Democratic voters in the dense areas and conservative Republicans in the rural parts of the state. Gordon Smith is quite conservative and Merkley, currently the speaker of the Oregon House, would likely rate as more liberal than the median Democratic Senator, were he to win the race.
Obama's strength in Oregon is bad news for Smith, who is probably cooked. He's no better than +180 and that's likely generous. Merkley's been known to have his missteps, so it's not out of the question he could blow it, but Oregon should be rid of its last Republican holding statewide office come January.