The deep-pocketed, fiscally conservative Club for Growth has endorsed Indiana State Treasurer Richard Mourdock's (R) bid to unseat longtime Sen. Dick Lugar (R-Ind.), a major boon for the right-wing challenger.

"After 36 years in Washington, it's time to send Richard Lugar home," said Club for Growth President Chris Chocola. "Richard Lugar has served honorably, but he’s been part of the problem in Washington. He's voted for bigger government, more spending, and he even recently voted against a permanent ban on congressional pork. Richard Mourdock will vote to limit government, repeal ObamaCare, and will help bring back the jobs lost to Obama's economic policies."

The group has long attacked Lugar, ran ads against him last year and put out a poll showing him and Mourdock in a close primary race. But it had adopted a wait-and-see approach on an actual endorsement over concerns Mourdock would not have the money to run a real race against Lugar.

Lugar is a top target of Washington-based conservative groups; Mourdock was already backed by FreedomWorks and Citizens United. But the Club for Growth has the ability to spend much more money than those other groups. Chocola, a former Indiana congressman, might take a personal interest in the race.

Lugar recently come under fire for primarily living in Washington, D.C. and voting at the address of a home he sold more than three decades ago. Mourdock has also tried repeatedly to tie him to President Obama.

But the longtime senator has a big cash advantage in the race and boasts the backing of most Republicans in the state, including popular Gov. Mitch Daniels. The early-May primary will be hard-fought.

Democrats hope Mourdock can upset Lugar, giving their candidate, Rep. Joe Donnelly (D-Ind.), a better shot at the seat.