When Evan Bayh suddenly retired on the eve of the deadline to qualify for the primary ballot, liberals immediately suspected that he'd screwed over  his party. (Matthew Yglesias: "He’s ditching his seat in a manner calculated to throw control of it to a conservative Republican.") But Republicans think Bayh was trying to screw them:

Republicans are livid about the timing of Sen. Evan Bayh’s (D-Ind.) retirement announcement.

They have at least four candidates in the upcoming primary while the Indiana Democratic Party will get to decide its nominee.

Bayh is tight with the Indiana Democratic establishment, and I suspect he was trying to help his party. But who knows? He works in strange and mysterious ways.