Nov. 20: Fifth Democratic primary debate, held in Atlanta. Klobuchar has qualified.
Dec. 19: Sixth Democratic primary debate, held in Los Angeles. The thresholds to qualify will be even higher.
January to April 2020: Six more Democratic primary debates will be held, including some in early-voting states.
Jan. 17: Early voting for presidential primary starts in Minnesota.
Feb. 3: Iowa caucuses. The results here will winnow the field.
Feb. 11: Primaries held in New Hampshire.
Feb. 22: Nevada holds Democratic caucuses.
Feb. 25: Precinct caucuses in Minnesota.