FreedomWorks PAC, the well-funded Tea Party organization chaired by former House Majority Leader Dick Armey (R-Texas), has endorsed Richard Mourdock in his primary battle with Sen. Dick Lugar (R-Ind.).

The endorsement adds another voice to the conservative push to unseat an incumbent Republican for being too centrist and supporting Democratic spending initiatives. Lugar has served in Congress for more than three decades, but has attracted Republican challengers due to his support for the Troubled Asset Relief Program and other votes.

“Over the past few months we have been speaking with our Indiana members and allies, including those affiliated with the Hoosiers for a Conservative Senate," said the PAC's executive director, Max Pappas. "Two things are clear: they want Richard Mourdock to be their Senator and they are going to do the hard work necessary to make it happen."

Mourdock, who serves as Indiana's state treasurer, also has presidential candidate Herman Cain and conservative group Citizens United behind his primary challenge against Lugar.