(CNN) — Republican Gov. Nikki Haley of South Carolina will announce Monday that she’s appointing GOP Rep. Tim Scott as Sen. Jim DeMint’s successor, according to Republican sources in South Carolina and Washington.
The announcement will come at noon ET at South Carolina’s state house in Columbia. Scott will become the Senate’s only African-American member and the GOP’s second African-American senator since Reconstruction.
DeMint announced earlier this month he would resign his from his Senate seat by January 1 to lead The Heritage Foundation, a leading conservative think tank in Washington.
Scott will fill the Senate spot until a special election takes place in November 2014, with the winner of that contest serving the remaining two years of DeMint’s second term.
Haley’s shortlist of contenders included Scott, along with Rep. Trey Gowdy, former state Attorney General Henry McMaster, former South Carolina First Lady Jenny Sanford and Catherine Templeton, a conservative attorney chosen by Haley to head the state Department of Health and Environmental Control.
Since DeMint’s retirement announcement, Scott emerged as a favorite of national grassroots conservatives. DeMint has long viewed Scott, a former state legislator who was first elected to Congress in 2010 with the help of tea party activists and national conservative groups, as a rising star and protégé.
Before making her selection, Haley said she would not consider a “placeholder” senator who would pledge to only hold the office until the special election.
“While there are some good arguments in favor of that approach, I believe the better case is against it,” she said in a statement last week.
The day after DeMint’s announcement, Haley vowed to pick his immediate successor quickly and choose someone “who has the same philosophy of government that Jim DeMint and I share.”
She also jokingly hit back against comedian Stephen Colbert, who expressed interest in running for the seat in his native state.
DeMint, a kingmaker among conservatives, is highly influential and well-beloved in the tea party movement, and has been a thorn in the side of establishment Republicans. In 2009, he was the first to endorse Marco Rubio of Florida in his 2010 Senate bid, at the time that the National Republican Senatorial Committee was backing Florida Gov. Charlie Christ.
He was also a powerhouse in the 2012 election. He held a highly-sought endorsement in congressional races and used his super PAC, Senate Conservatives Fund, to back tea party favorites in GOP primaries. Among his picks were successful Senate newcomers Ted Cruz of Texas, Jeff Flake of Arizona and Debbie Fischer of Nebraska.
“I know I’m leaving the Senate better than I found it with some real leaders,” DeMint said, referring to his role in “stocking the Senate with solid conservatives.”
CNN’s Paul Steinhauser, Sam Feist, Mark Preston, Kevin Liptak and Ashley Killough contributed to this report.