Candidates who qualified for January’s debate. Photos: Amr Alfiky/NPR (Sanders); Getty Images (Steyer); Olivia Sun for NPR (Buttigieg); U.S. Senate (Klobuchar and Warren); White House (Biden)

Candidates who qualified for January’s debate. Photos: Amr Alfiky/NPR (Sanders); Getty Images (Steyer); Olivia Sun for NPR (Buttigieg); U.S. Senate (Klobuchar and Warren); White House (Biden)