[aruanan]

You can’t impeach over this. It’s at most a misdemeanor, and not very high at that.

You can impeach over "high crimes and misdemeanors," in other words, over a whole range of behavior unbecoming the office.

[AuH2ORepublican]

Actually, you can impeach for “Bribery and other High Crimes and Misdemeanors.” If Obama promised to name Sestak Secretary (or Undersecretary) of the Navy in return for Sestak dropping out of his race against Specter then Obama was either offering or willing to accept a bribe.