I still think the title is up for grabs, but for just being plain dumb, you have to give a slight edge to Barbara Boxer and Patty Murray. Those two take stupidity to new levels everytime they open their mouths, although Durbin gets about 1,000 points on the BS Meter for his latest verbal flatulence.
There is tough competition for that titile-stupidest Senator. I would have thought Biden. Was he drunk when he made those comments? Then given a chance to take it back he repeats it. Yeah, stupid.