Republican Sen. Richard Lugar of Indiana said Tuesday he plans to seek a seventh term in 2012 despite a challenge from Tea Party groups.

Lugar, 78, told reporters Tuesday at a breakfast hosted by The Christian Science Monitor in Washington that he takes the opposition seriously.

Representatives from more than 50 tea party groups plan to meet Saturday in Tipton to discuss strategies to beat Lugar in next year's GOP primary.

Lugar's spokesman, Mark Helmke, said the senator plans to run a vigorous campaign and is committed to winning a seventh term representing Indiana in the Senate. Lugar was first elected to the Senate in 1976.

He plans to return to Indiana on Friday for a major fundraiser in Carmel, outside of Indianapolis. Helmke says Lugar has already raised more than $320,000.

Lugar has carved out a bipartisan reputation during his decades in Washington, working with Democrats on a variety of issues, particularly foreign policy initiatives. That could make him vulnerable to a potential challenge from a Tea Party challenger on the right.

His support for such things as the DREAM Act, which would help some illegal immigrants who came to the U.S. as children obtain a path to citizenship, and his votes for President Barack Obama's Supreme Court nominees have upset many conservatives in Indiana, particularly those aligned with the tea party movement. He has also supported the New START arms reduction treaty signed by Obama and Russian President Dmitry Medvedev in April.

Two Republicans mentioned as possible challengers to Lugar are State Treasurer Richard Mourdock and state Sen. Mike Delph of Carmel.