(CNN) - South Carolina Rep. Henry Brown, a five-term Republican, is set to announce his retirement Monday, two sources tell CNN.
Brown, whose 1st Congressional District includes much of South Carolina's coastline –including Charleston and Myrtle Beach - won a closer-than-expected reelection bid in 2008 and was already set to face a primary challenge from Carrol Campbell III, the son of a once powerful South Carolina Republican.
The news was first reported by the Palmetto Scoop.
But while Brown only won his reelection bid by 4 points in 2008, his district is considered to be reliably conservative, handing then-Republican Presidential Candidate John McCain 56 percent of the vote in 2008.
According to the Palmetto Scoop, at least three other Republicans besides Campbell have announced their intention to run for Brown' seat, including Mt. Pleasant Town Councilman Mark Fava.
Paul Thurmond, the son of the longtime Sen. Strom Thurmond, and Tim Scott, a current State Representative who is currently making a bid for lieutenant governor, could also enter the race.
Brown becomes the second Republican in as many weeks to announce his plans to retire from the house without aspirations for any other office.
Rep. George Radanovich of California announced his retirement last Tuesday, saying he would forego a run for a ninth term in the House to spend more time with his wife, Ethie, who has been fighting ovarian cancer for the past three years.
In November and December, four House Democrats announced they would retire at the end of 2010 rather than run for re-election.
- CNN's Alexander Mooney contributed to this report