House Majority Whip Roy Blunt (R-Mo.) announced today that he has appointed Brian Gaston to be his chief of staff effective Friday. Gaston, who worked for then-Majority Leader Dick Armey (R-Texas) before joining Blunt’s staff in January 2003, will take over for Dave Hebert.

There had been rumors in GOP circles for months about potential changes in Blunt’s staff, mainly focused on Hebert. These sources said Blunt had actually made his decision to replace Hebert several weeks ago but held off in order to allow Hebert time to find a new employer. Hebert, who had only been on the job for nine months, “is considering a number of public and private sector opportunities,” according to a statement put out by Blunt’s office.

Blunt’s longtime chief of staff, Gregg Hartley, left last summer, at which time Hebert was brought in. According to some GOP insiders, Hebert never meshed comfortably with the Whip operation, and there were signs earlier in the year that Blunt was going to make a move. Blunt decided to elevate Gaston recently, said Republican sources, and the only issue that remained was timing.

“We had always envisioned this as a short-term assignment to get the Whip office up and operational,” Hebert said in a statement released by Blunt’s office. Hebert, a longtime lobbyist, joined Blunt’s staff after eight years with the American Association of Nurse Anesthetists.

Gaston is a long-time Republican leadership aide with extensive experience on Capitol Hill.

“Brian is a trusted member of my staff and helped get our Whip operation off to a great start,” said Blunt in the statement. “The entire Whip operation will benefit from his policy expertise, incredible institutional knowledge and wealth of contacts. I’m pleased that he has agreed to accept his new responsibilities.”

The 43-year-old Gaston, an Ohio native, broke into politics in 1984 as a legislative correspondent for then-Sen. Charles Percy (R-Ill.). Gaston worked from 1985 to 1989 as legislative director for then-Rep. Harris Falwell (R-Ill.) before becoming administrative assistant and press secretary for then-Rep. Jan Meyers (R-Kan.).

In 1993, Gaston joined Armey’s staff as director of member services, which was followed by a four-year stint beginning in 1995 as deputy chief of staff/policy director for then-House GOP Conference Chairman John Boehner (Ohio). In 1999, Gaston returned to Armey’s office as policy director, a post he held until the Texan retired from the House at the end of the 107th Congress.

Although Gaston has been heavily wooed by K Street, he wanted to stay on the Hill and was recruited by Blunt to be deputy chief of staff and policy director in the Whip’s office at the start of the 108th.

“Brian is a hard worker and an honest broker,” said Bob Schellhas, a lobbyist with Citigroup who worked for Boehner at the same time that Gaston served in the Ohio Republican’s leadership office. “He has an incredible amount of experience on the Hill.”

Gaston takes over a leadership operation that has taken some hits over the last year, although Blunt’s defenders are quick to point out that he has never lost a vote as Majority Whip.

Blunt has had several bouts with cancer since 2002, including having a kidney removed, although his health is good now, said sources close to the Missouri Republican.

Blunt’s April 2003 divorce from his wife of 35 years became a political issue after The Washington Post reported in June 2003 that Blunt had quietly tried to insert a provision in earlier legislation creating the Homeland Security Department that would have aided tobacco giant Philip Morris. Blunt was personally close to Abigail Perlman, a lobbyist for Philip Morris, and the two later got married. Despite complaints from House Democrats about the controversy, it never developed into a full-blown ethics investigation.