The Senate as expected overwhelmingly confirmed longtime Sen. Max Baucus to be ambassador to China on Thursday, amping up speculation on who will replace him and creating a power shift at the committee level.

The Montana Democrat, who has served in Senate since 1978, initially had planned to retire when his term expired next January. But in a move that surprised many, President Obama announced in December he wanted Baucus -- who was instrumental in helping shepherd Obama's health care law through the Senate in 2010 -- to represent the U.S. in Beijing.

Baucus, 72, who has been chairman of the powerful Senate Finance Committee since 2007, said he was "humbled" by the opportunity.

"The relationship between the U.S. and China is one of the most important in the world, and we, both China and the United States, need to get it right," he said.

In a chamber often wrought with partisan gridlock, the Senate approved the Democrat's nomination by a vote of 96-0. Baucus voted "present."

"His passion is well known to all of us, his decades of experience here in Congress," said Senate Majority Leader Harry Reid, D-Nev. "He's an excellent choice that President Obama made to represent America's interests in China."

Montana's Democratic Gov. Steve Bullock will appoint a replacement to fill out Baucus' term. But with Lt. Gov. John Walsh already running for Senate, there isn't a clear frontrunner.

The governor has scheduled a news conference for Friday.

Baucus' Senate exit also opens the door for another Democrat to assume control of the Senate Finance Committee, with Sen. Ron Wyden of Oregon the expected successor. Wyden, in turn, likely would give up his chairmanship of the Senate Energy and Natural Resources Committee to Sen. Mary Landrieu, D-La.

Baucus, a moderate Democrat, over the years has reached across the aisle on major issues. He supported President George W. Bush's sweeping 2001 tax cuts and his 2003 creation of Medicare prescription drug benefits. And recently the Montanan had been working with Republicans on income tax reform.

"Max is a friend and has been a good partner on many resource, trade and transportation issues over the years" said Sen. Mike Crapo, R-Idaho. "I wish Max nothing but the best as he continues his public life as the next ambassador to China."