U.S. Senator David Vitter has thrown his support behind fellow Repubican Attorney General Buddy Caldwell in his re-election bid.
Vitter cited Caldwell's opposition to the new federal  health-care law and support for tougher  immigration enforcement laws among the reasons. The only announced challeger so far is former U.S. Rep. Joesph Cao, a Republican from New Orleans.  Qualifying for the  Oct. 22 primary is in September.