(CNN) - Add another prominent Republican to the list of conservatives and conservative organizations who have endorsed Delaware Senate candidate Christine O’Donnell.
South Carolina Sen. Jim DeMint announced Friday night his endorsement of the Tea Party-endorsed candidate. His backing follows similar announcements in recent days from former Alaska Gov. Sarah Palin, the Tea Party Express and the National Rifle Association.
"I’m proud to endorse Christine O’Donnell for U.S. Senate in Delaware," DeMint wrote Friday on his Twitter page. "She will stand strong for the principles of freedom."
DeMint, a conservative senator whose name has been floated as a possible 2012 contender, has unveiled a number of endorsements in recent months that have pitted him against either the GOP establishment or former Alaska Gov. Sarah Palin.
O'Donnell is locked in a battle for Delaware's GOP nomination with centrist Rep. Mike Castle, who has the party establishment’s backing.
The GOP primary in Delaware will be held on Tuesday.