Senate Democratic Leader Harry Reid said on Friday he will retire next year and swiftly threw his weight behind New York Senator Chuck Schumer to replace him as leader.

"I think Schumer should be able to succeed me," Reid said in an interview with The Washington Post, referring to the selection of the next head of the Senate Democratic caucus, a post that will be filled after November 2016 elections.

Reid's decision muddies the outlook for the Democratic Party as it seeks to retake control of the Senate in 2016. He had a tough re-election fight in Nevada in 2010 and it is unclear what impact his departure will have on Democrats' ability to hold the seat.

The Democrats hold 44 seats in the Senate. Republicans hold 54 seats and independents two.

Reid, who is 75, said Schumer, now the No. 3 Senate Democrat, would probably win the caucus' top post without opposition. He said the other likely contender, Illinois Senator Dick Durbin, would probably defer to Schumer, according to the newspaper report. Durbin has the caucus' No. 2 spot now.

There was no immediate comment from either Schumer or Durbin's office on the Post report.

Reid said earlier in a video message his decision not to seek re-election was not due to a recent exercising accident or his party's loss of control of the Senate in congressional elections last November.

A former amateur boxer who represented Nevada in the Senate and the House of Representatives, Reid vowed to keep fighting for his party in his remaining 22 months in office.

In January, Reid suffered broken ribs and facial bones when exercise equipment broke as he was using it. On Friday, he said the "down time" caused by the mishap had given him time to ponder Democrats' future.

"We have to make sure that the Democrats take control of the Senate again," he said in the video. Known as a prodigious fundraiser, Reid added that re-election resources can now be used to help other Senate Democrats instead of himself.

Schumer, 64, who was elected to the Senate in 1998, has a strong appetite for publicity and successfully worked to expand the number of Democrats in the Senate as head of the Democratic Senatorial Campaign Committee from 2005 to 2009.

A former Senate Democratic aide noted that over the past several years a "closeness that developed over time" had become apparent between Reid and Schumer, with the two working together on legislative and messaging strategy.

But Schumer is also known as a friend of Wall Street, which could put him at odds with the more liberal wing of the party represented by Durbin as well as newcomer Massachusetts Senator Elizabeth Warren, elected in 2012.

"There are a lot of good people on that progressive bench that could run (for Senate Democratic leader). Warren is definitely one of the top names to be discussed. Dick Durbin is another," said Neil Sroka, communications director for progressive group Democracy for America, in a phone interview.

However, Warren will not be a candidate for Senate leader in 2016, a spokesman for her Senate office said.

There was already some liberal backlash to a Schumer candidacy. On Friday, the liberal group MoveOn.org said Schumer's support for two pieces of Iran-related legislation should disqualify him from leading the Senate Democratic caucus.