Tea Party supporters that helped the Republicans win a U.S. House majority last year also prevented the party from taking control of the Senate and could do it again in 2012, Senator Richard Lugar said.

Lugar, 79, an Indiana Republican, said his seat could be in danger if he loses a primary next year to state Treasurer Richard Mourdock, who is backed by Tea Party groups. U.S. Representative Joe Donnelly is seeking the Democratic nod.

“Republicans who are running for re-election ought to be supported by people who want to see that majority,” Lugar said Sunday on CNN’s “State of the Union.”

Lugar characterized the Tea Party groups as “very conservative Republicans” and said that he had “a very conservative voting record” in the Senate deserving of their support.

His campaign website touts his opposition to President Barack Obama’s health-care law, which provides coverage for millions of uninsured Americans, and his support for a national sales tax instead of the progressive income tax that requires the wealthy to pay more.

He mentioned Nevada and Colorado as two states where Tea Party-backed Senate candidates won Republican primaries last year before losing the general election to Democratic incumbents. Senate Majority Leader Harry Reid defeated former state legislator Sharron Angle in Nevada and Sen. Michael Bennett beat county prosecutor Ken Buck in Colorado.

“There were people who claim that they wanted somebody who was more of their Tea Party aspect, but in doing so they killed off the Republican chances for majority,” Lugar said. “This is one of the reasons we have a minority in the Senate right now.”

Mourdock, 60, is backed by a coalition of Tea Party groups, Hoosiers for a Conservative Senate. He also has the support of the political action committee of FreedomWorks, the Tea Party- aligned group led by former House Majority Leader Dick Armey of Texas.

Mourdock’s campaign website criticizes Lugar for supporting the Troubled Asset Relief Program, passed under Republican President George W. Bush to bail out the financial industry; and for supporting federal aid for General Motors Co. and Chrysler Group LLC, an Obama administration program that saved both companies.

Democrats now hold a 53-47 edge in the Senate, including two independents who caucus with them.

Through Sept. 30, Lugar’s campaign had $3.8 million in the bank, compared with $291,640 for Mourdock, Federal Election Commission reports show.