Evan Bayh is bowing out. From the Hotline:

Sen. Evan Bayh (D-IN) will not seek a 3rd term in the Senate next year, according to a Dem source, handing Dems yet another setback as they struggle to salvage their damaged ship.
Bayh, elected statewide 5 times, will become the 5th Senate Dem not to seek another term. His decision to step aside , first reported by The Fix and confirmed to Hotline OnCall, creates an open seat in IN, a usually-red state that broke the mold in ‘08 by voting narrowly for Pres. Obama.
Last week, ex-Sen. Dan Coats (R), who held Bayh’s seat before retiring in ‘98, announced he would run for the seat. Ex-Rep. John Hostettler (R) had already announced his own candidacy.
A recent poll taken for the liberal DailyKos website showed Bayh easily beating both Coats and Hostettler. And Bayh ended the year with $13M in the bank, far ahead of any potential challengers.

Update: Yes, Kathryn beat me to it, again.