Kevin Tyne, right, the governor's chief of staff will leave the office in three weeks after intense, behind-the-scenes criticism of his management style/Capitol Media Serices file photo.

Gov. Jan Brewer has finally given in to the growing political pressure to replace her closest adviser. Chief of staff Kevin Tyne will leave the state Capitol in three weeks to take a post with the Republican Governors Administration, Brewer announced on her Facebook page this morning. (Various media outlets starting blogging and tweeting about Tyne’s pending departure an hour earlier.) His replacement will be deputy chief of staff Eileen Klein. Brewer’s announcement came a few hours before Brewer is scheduled to meet with  House Speaker Kirk Adams, R-Mesa, and Senate President Bob Burns, R-Peoria, to plan a possible November special session to address a $1.5 billion budget deficit.

Tyne has been at Brewer’s side for years, going back to her days as a Maricopa County supervisor. He was quite as effective as her deputy when Brewer was secretary of state. So he was the natural choice to take on the day-to-day chores of managing Brewer’s administration when she became governor in January.

But Tyne has been a focus of lots of criticism behind-the-scenes this year. As the Arizona Guardian recently reported (story is subscription-only), Tyne has received much of the blame for Brewer’s challenges in dealing with a Legislature controlled by her own party. Lawmakers claimed they were frequently blindsided by Brewer’s positions and maneuvering on budget issues.

As I read the complaints (and I have heard my share from Capitol sources), Tyne became a target partly because Brewer was once an accomplished state senator. Many political insiders can’t imagine she has forgotten that much since her time in the legislative halls. So if Brewer’s administration can’t get things done, it must be Tyne’s fault as her right hand, so the thinking seems to go. That’s point of view gets a boost with Klein moving up. She is a former chief of staff for the state House who has her own reputation for being tough but is among the most knowledgeable anywhere about the details of the state budget.

But Brewer is loyal to her friends and allies. Until today, she gave every indication she was going to keep Tyne despite the private efforts to push him out. It’s possible that Tyne is being a good soldier and he volunteered to step aside to help Brewer repair her relations with Republican lawmakers.

There’s also been some speculation this is a sign that Brewer will run for election next year. I wouldn’t go that far. Brewer has done almost nothing to prepare for a tough statewide primary, and she’s quickly running out of time to get a campaign organization off the ground.

UPDATE: Jan Brewer’s longtime public relations firm and campaign managers at HighGround of Phoenix have issued a statement coming to Kevin Tyne’s defense. Key quote: “It shouldn’t be a surprise today that politicos will attempt to assign blame to Kevin Tyne, but the reality is that Kevin was an equal to any Chief of Staff who has served any previous Arizona Governor.”