Indpendent favored in Maine Senate race, conservative super PAC tied to RGA helps out Democratic opponent.

Patriot Majority USA kicks off long-term campaign targeting billionaire Koch brothers

Restore Our Future sitting on $20 million-plus

Conservative nonprofit American Future Fund attacks Senate candidates in Florida and Wisconsin

Tallies from the first two weeks of August show the super PACs and outside groups backing Mitt Romney are vastly out-spending the president's main political action committee.

Crossroads GPS hits North Dakota's Heitkamp with the second round of ads in as many weeks

Heavy-hitting outside groups release five negative ads in 24 hours

AFL-CIO super PAC goes after Romney and Ryan on coal and Medicare

Former steel mill worker links wife's cancer death to Bain buyout

Missouri primary race next up