TX-21: Tom DeLay to Drop Out

Darnit. Bush won this district 61%-39% in 2004 and 66% to 33% in 2000. DeLay dropping out will make it a bit harder to pickup his seat. CNN:

Rep. Tom DeLay will drop out of his re-election race, two Republican congressional sources told CNN Monday.

DeLay was forced to step down as House majority leader last year after being indicted in his home state of Texas.

DeLay told Time magazine Monday that he and his wife, Christine, had been prepared for an election battle, but that he decided Wednesday to spare his suburban Houston district the mudfest to come.

He did it for his district. Yeah, right.

Question: What's the procedure for getting a new candidate on the ballot in Texas after the candidate who won the primary drops out? And can Democrats do this for Texas state senate district 18?

UPDATE: It looks like others have been thinking about this: Swing State Project, DeLay v World, Daily Kos, Burnt Orange Report, and Off the Kuff. The upshot seems to be that DeLay can be replaced on the ballot.