In an appearance Thursday on MSNBC's "Morning Joe," Chicago Mayor Rahm Emanuel said that in 2020, Democrats should support a proven winner instead of a "loser" like Rep. Beto O'Rourke (D., Texas).

"If Beto O'Rourke wants to go and run for president, God bless him. He should put his hat in and make his case. But he lost. You don't promote a loser to the top of the party," Emanuel said.

Despite previous insistences that he was not interested in higher office, O'Rourke told reporters on Monday he would not rule out a 2020 run. The Texas Democrat received extensive national attention during his failed Senate bid against Sen. Ted Cruz (R., Texas), shattering fundraising records while losing by 3 points.

Emanuel, the former Democratic Congressional Campaign Committee chair, said he wanted someone who understood riding the momentum of a successful midterm to a White House win.