Sen. Al Franken plans to leave the Senate on Jan. 2, ending his tenure in the chamber with nearly three years left in his term and after he started 2017 being regarded as a possible presidential contender.

Last week, Minnesota Gov. Mark Dayton said he would appoint the state’s lieutenant governor, Tina Smith, to fill Franken’s seat until a 2018 special election. 

Smith said she will run for the remainder of Franken’s term, which is up in 2021. The special election will be held concurrently with next year’s midterms, when Democratic-Farmer-Labor Sen. Amy Klobuchar also faces voters.

Franken announced on Wednesday that he would be doing a “series of final speeches” on the Senate floor.

“When I leave the Senate in a few weeks, I’ll continue trying to be an educated citizen, and an advocate, and an activist,” he said during his first speech. “But over the last eight-and-a-half years, as I’ve had the privilege of serving the people of Minnesota, I’ve also gained a new perspective on the issues we face and the way we here in Washington make decisions.”

Franken announced his resignation after a number of women came forward alleging sexual misconduct against the former writer for Saturday Night Live. Since that announcement, some Democrats, including Sen. Patrick J. Leahy of Vermont, said a full investigation by the Senate Ethics Committee should have occurred first.

“I have stood for due process throughout my years as a prosecutor and in chairing the Judiciary Committee,” Leahy said in a statement. “I regret not doing that this time. The Ethics Committee should have been allowed to investigate and make its recommendation.”