(CNN) - Montana Lt. Gov. John Walsh now has the job he's already been running for: U.S. senator.
Montana Democratic Gov. Steve Bullock Friday named Walsh, a fellow Democrat, to fill the remainder of the term of Sen. Max Baucus, who was overwhelmingly confirmed Thursday as U.S. ambassador to China.
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"Today my friend and my colleague embarks on a new mission. I introduce to you United States Sen. John Walsh," said Bullock at a news conference in the state capitol building in Helena.
Baucus, a six-term Democratic senator, announced last April that he would retire at the end of 2014 rather than run for re-election. In October, Walsh announced his bid to try to keep the seat in party hands.
Late last year the White House announced it would nominate Baucus as U.S. ambassador to China, spurring speculation that Bullock would name Walsh to serve as interim senator. The power of incumbency gives Walsh better name recognition and an easier ability to raise campaign cash. That will come in handy as Walsh prepares to fend off a primary challenge from former Lt. Gov. John Bohlinger.
And it will also help in the general election. With Baucus gone, Republicans see Montana, a state that leans conservative, as a strong pickup possibility in November midterms. The GOP needs to win back six Democratic held seats to reclaim control of the Senate. The have a strong candidate in Rep. Steve Daines, the likely Republican nominee.
At the news conference, Walsh touted his bipartisan efforts and mentioned Daines as well as Montana's other senator, Democrat Jon Tester.
"Sen. Baucus does leave big boots to fill," said Walsh. "I know that working with Sen. Tester and Congressman Daines, we can meet those challenges."
Many Republicans argue that with the approval ratings for Congress at or near all time lows, sending Walsh to Washington may backfire on the Democrats.
"John Walsh, He's Already Gone Washington," said the headline of an email sent to reporters by America Rising, a pro-GOP opposition research shop.
And national Republicans were quick to tie Walsh to President Barack Obama and Senate Majority Leader Harry Reid.
"Harry Reid and President Obama have pulled all the strings they can to clear the way for their hand-picked, scandal-plagued choice John Walsh," said the narrator in a new commercial by the National Republican Senatorial Committee that is expected to run on-line for two weeks.
Serving in the Senate will also give Walsh a voting record, which could also be used against him by Republicans.
Walsh, 53, served as an adjutant general in the Montana National Guard, spending time in Iraq. His first run for office was in 2012, when he won election for lieutenant governor on the same ticket as Bullock.