A brief look at the 5 candidates who will take the stage at 8:30 p.m. Eastern on CNN. For more on the candidates running for their party's 2016 nominations, check out our election primer: http://nyti.ms/1LsUUox
  1. Hillary Rodham Clinton
    Clinton is working to corral the party establishment behind her, as she finds her wide lead being narrowed by Bernie Sanders.
  2. Bernie Sanders
    Sen. Sanders has drawn enthusiasm among voters who were craving a more liberal option in the Democratic mix.
  3. Martin O'Malley
    The former Maryland governor is pushing his youth and vitality as an asset.
  4. Jim Webb
    Webb, who was a senator from Virginia, has been a persistent critic of the Iraq war but tends to hold more conservative views on gun control and immigration.
  5. Lincoln Chafee
    A Republican-turned-independent-turned-Democrat from Rhode Island, Chafee is most passionate about national security.