The American Action Network, a super-PAC that backs establishment Republicans, has pulled out of Indiana’s Senate race, the latest bad omen for Sen. Richard Lugar (R-Ind.).

“We’ve decided we’re going to let this race play out,” AAN spokesman Dan Conston told The Hill Friday evening.

The group had committed to spending nearly $600,000 on television attacking Lugar’s Tea Party opponent, Indiana state Treasurer Richard Mourdock (R), and has been on the air in Indianapolis for two weeks. But they have pulled their online advertising and will end their TV buy on Tuesday, a week ahead of the May 8 primary.