President Bush is losing two more key aides as his presidency winds toward its end, with his chief speechwriter and lobbyist both announcing Friday that they are leaving.

Speechwriter William McGurn will be succeeded by his deputy, Marc Thiessen, a one-time speechwriter for former Defense Secretary Donald H. Rumsfeld.

Legislative affairs director Candida Wolff will be succeeded by Dan Meyer, who joined the White House lobbying team last March. He has extensive experience as a staff member in the House and Senate.

The last high-level departures from Bush’s team came just two weeks ago, when his top economic adviser announced he would be leaving. National Economic Council director Al Hubbard is being replaced by his deputy, Keith Hennessey.

The list of other aides, confidants and Cabinet members who have left or soon will includes Rumsfeld, Attorney General Alberto Gonzales, political adviser Karl Rove, press secretary Tony Snow, terrorism adviser Fran Townsend and senior adviser Dan Bartlett.

Bush issued statements of praise for Wolff and McGurn.

“One of the most challenging jobs in any White House is managing the president’s relationship with Congress,” the president said. “There are 535 members of Congress, 2 parties, and 46 committee chairmen but only one assistant to the president for legislative affairs. Candi Wolff has done a remarkable job of working with Congress and advancing my legislative agenda.”

Bush said McGurn “has worked tirelessly to help communicate my agenda to the American people and the world. Bill is a serious thinker and a gifted writer whose command of language and knowledge of history have helped shape a wide variety of my speeches.”

Presidential spokesman Scott Stanzel defended the White House against the perception that it is being drained of its top talent, noting that Bush has recently recruited experienced Washington hands such as Ed Gillespie and Fred Fielding onto his staff. Gillespie is White House counselor; Fielding is White House counsel.

“The president continues to draw very talented people to his team, even in the late stages of his administration,” Stanzel said. “There was a general understanding that there’s a period of time in which people would consider leaving.”

McGurn, a former Wall Street Journal columnist and chief editorial writer, took a low-profile approach to the job he assumed in early 2005. Stanzel said he would stay on until after Bush’s final State of the Union address in late January, the White House’s signature speechwriting event of the year and typically the most arduous.

Like McGurn, Wolff also took over her post around the start of Bush’s second term, becoming Bush’s chief liaison to Capitol Hill after doing the same job for Vice President Dick Cheney. She is leaving at the end of the year, Stanzel said.