Citizens United Political Victory Fund on Wednesday backed Indiana Treasurer Richard Mourdock’s (R) bid to oust Sen. Dick Lugar (R) next year.

Mourdock’s campaign said the national conservative group endorsed him after Lugar voted for the debt ceiling agreement earlier this week. Mourdock said in a statement that he would have opposed the debt deal because “it did nothing more than kick the ‘tin can of responsibility’ further down the road and set the stage for a future tax increase by the new debt ‘super committee.’”

Lugar, who has a sizable cash advantage over Mourdock, is vulnerable in the GOP primary. However, the Club for Growth has not yet endorsed Mourdock in the race.