The latest news on Donnelly, Joe
In Senate recess, Bloomberg and other Mayors Against Illegal Guns run ads on background checks.
He won his primary as a tea party candidate, but now Mourdock moves to the middle.
Members of Weiner's own party have called for his ouster in light of lewd Twitter picture scandal.
New polls show vulnerable House Democrats as well.
The tactic could hurt Democratic turnout when the party needs to protect its majority in Congress.