Guilty, guilty, guilty!

Good riddance to a pork-barrel Republican:

Alaska Sen. Ted Stevens has been convicted of lying about free home renovations and other gifts he received from a wealthy oil contractor.
The Senate's longest-serving Republican, Stevens was found guilty on all seven counts of making false statements on Senate financial documents.
The verdict throws the upcoming election into disarray. Stevens is fighting off a challenge from Democrat Mark Begich and must now either drop out or continue campaigning as a convicted felon.

Why didn't Stevens resign months ago? This is the same question I asked with Bob Ney two years ago. Where do these Republicans get the idea they can survive scandals like this?