There is no benefit of the doubt needed, the MAJORITY LEADER said she was voting to send the bill to committee in order to KILL it, and the same thing happened the previous year with impeachment for the VP.
The Democrats were looking at an election where the surge had started to work and they had an anti-surge candidate; they also had a base opposed to a war that they had not been able to stop.
They didn’t want an impeachment vote they knew their own caucus couldn’t afford to support.
Most republicans decided it would be fun to play politics with the vote. A few decided impeachment was too important to play politics with. I don’t fault those who wanted to bring it to a vote to kill it, but I’m not stupid enough to think those who voted to kill the bill wanted it to pass.
I know Ron Paul loves anything that comes from Kucinich's tiny, demented brain and I assume he voted for it.