The Senate chose its leaders for the new term.
Senate Republicans have re-elected Mitch McConnell to be Majority Leader come January.
McConnell will be a key legislative partner for President-elect Donald Trump.
He served as Senate Minority Leader for eight years, before becoming majority leader in 2015.
McConnell distanced himself from Trump during the presidential campaign, but now says he is ready to work with him.
Senate Democrats have elected Chuck Schumer as their new Minority Leader.
He will replace Harry Reid, the Nevada Democrat who’s retiring after 30 years in the Senate.