The majority and minority leaders of Senate will serve at least two years under Donald Trump's upcoming presidency, barring unforeseen circumstances.
McConnell's spokesman, Don Stewart, said the Kentucky senator was re-elected unanimously with "a standing ovation" from his colleagues. No senator publicly challenged McConnell for the position.
Republican senators will hold a private meeting on Wednesday to elect their leadership team for the coming year.
On the other side of the aisle, Schumer will replace Sen. Harry Reid, D-Nev., who is retiring after serving as a senator for 30 years. During a press conference, the New York senator announced his leadership team, which includes Sens. Bernie Sanders, Elizabeth Warren, Dick Durbin and Patty Murray.
"We need to be the party that speaks to and works on behalf of all Americans, and a bigger, bolder sharper-edged economic message that talks about how people in the middle class and those struggling to make it there can do better, but also deals directly with the unfairness in the American economic system," Schumer said.
On Tuesday, House Republicans re-elected Wisconsin Rep. Paul Ryan as speaker of the House. House Democrats delayed their leadership vote until Nov. 30 in order to evaluate the party's future in the chamber.