Senate Finance Committee Chairman Max Baucus (D-Mont.) plans to announce that he will retire rather than seek reelection in 2014, according to Democratic strategists familiar with his plans, ending one of the most influential congressional careers of his generation.

Baucus, 71, first elected in 1978,has been the top Democrat on the powerful committee since 2001. At times infuriating his Democratic colleagues, Baucus worked with Republicans to co-write the Bush-era tax cuts and the Medicare prescription drug plan, but he also served as the lead defender against George W. Bush’s 2005 effort to partially privatize Social Security and played a critical role in writing President Obama’s national health-care plan.

Baucus, from conservative-leaning Montana, has voted against Democratic initiatives on some social issues, most recently last week’s effort to create an expanded background check system for gun purchases. Republicans have been trying to land a top recruit to challenge Baucus, who despite his unpolished public image has been one of the savviest political operators among Mountain West Democrats.

He repeatedly won tough reelection battles and graduated from his staffs some of his party’s most influential political advisers and K Street lobbyists, establishing a Baucus alumni network that was envied by other senators and reviled by ethics watchdogs.

Despite Obama’s double-digit defeat in Montana, Democrats intend to vigorously defend the seat. The leading potential Democratic candidate is former governor Brian Schweitzer, a popular figure who at times has feuded with Baucus over local political issues in the Big Sky state. In February, Schweitzer hinted at a potential run in a Facebook post.

Emerging from a private huddle with members of the Finance Committee, Baucus acknowledged the news but declined to formally confirm it, saying he had to go address his staff. "You guys are really good. You get wind of stuff awfully quickly," Baucus told reporters. "Which means it's sort of changed my schedule today. ... I've got people I need to talk to first."

The Baucus retirement also could have dramatic policy consequences. No longer bounded by his own 2014 reelection, Baucus can now push for comprehensive tax reform without concerns about the political ramifications, his allies say.

He and Rep. Dave Camp (R-Mich.), the term-limited chairman of the House Ways and Means Committee, could jump-start tax reform with both men looking toward their legislative legacy rather than their political fallout within their respective caucuses.

Baucus’s offfice has been in touch with Camp's advisers and the two chairmen are expected to speak later Tuesday, advisers said.

His retirement is the latest blow to the Senate’s tradition of “Old Bulls," the powerful committee chairmen who in the past ruled their panels with strong determination and a freedom from party leaders.

In the past several months, Baucus has been in an open feud with Majority Leader Harry M. Reid (D-Nev.) and Sen. Charles E. Schumer (D-N.Y.), a member of leadership and senior Finance Committee member, over tax reform. Baucus has been willing to proceed with a plan that would eliminate loopholes and deductions to use that additional revenue for a broad-based lowering of corporate and personal tax rates.

Reid and Schumer want to use that revenue from loophole closing to reduce the deficit. Inside the Democratic caucus, many junior Democrats have chafed at Baucus’s power on finance, pushing leadership to rein him in, and some have even promoted the prospect of imposing term limits on chairmen. Those proposals have so far been brushed aside by Reid’s leadership team.

Baucus joins five other committee chairmen who have decided to retire rather than run for reelection, including Sens. John D. “Jay” Rockefeller (D-W.Va.), 75, chairman of the commerce committee, and Tom Harkin (D-Iowa), 73, chairman of the health committee. In the 2010 and 2012 election seasons, several other chairmen, including Chris Dodd (D-Conn.) and Kent Conrad (D-N.D.), opted to retire.

In recent years, longtime committee chairmen Robert C. Byrd (D-W.Va.), Daniel Inouye (D-Hawaii) and Edward M. Kennedy (D-Mass.) have also died in office.

In a statement Tuesday afternoon, Obama thanked Baucus for his service. "As Finance Committee Chairman and a senior member of both the Agriculture and the Environment and Public Works Committees, Max has been a leader on a broad range of issues that touch the lives of Americans across the country. Michelle and I commend Senator Baucus on his career, and wish him and his family well in the future," Obama said.

Baucus’s advisers said that he was not afraid of running another tough race. Already in his 70s, he faced a commitment that would have meant serving until he was 79.

In a signal that he was ready to spend time away from the Senate, he and his wife, Melody, have recently begun building what is considered a dream home outside Bozeman, Mont. Additionally, several of his closest advisers left their senior positions in recent months for private sector jobs in the lobbying industry.

Republican strategists began circulating stories about Schweitzer and his work stumping for Obama immediately after The Washington Post broke the news about Baucus’s retirement. Democrats rejected the idea that tying Schweitzer – or any Montana Democrat – to Obama would suffice in defeating him, citing the string of Senate victories for Democrats there that included the 2012 victory of Sen. Jon Tester (D-Mont.).

“Max Baucus has shaped and guided legislation and policy affecting every American, and his service has been a benefit to all Montanans. He has been an invaluable leader in our caucus, and he will be sorely missed. Democrats have had a great deal of electoral success in Montana over the last decade, and I am confident that will continue,” Sen. Michael Bennet (D-Colo.), chairman of the Democratic Senatorial Campaign Committee, said in a statement.

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