The road ahead
Through Nov. 20: Filing period for New Hamsphire primary
Nov. 10: Republican debate in Milwaukee
Nov. 14: Democratic debate in Des Moines
Dec. 15: Republican debate in Las Vegas
Dec. 19: Democratic debate in Manchester, N.H.
Jan. 17: Democratic debate in Charleston, S.C.
Feb. 1: Iowa caucuses (both parties)
Feb. 6: Republican debate in New Hamsphire
Feb. 9: New Hampshire primary (both parties)
Feb. 10: Republican debate in Florida
Feb. 13: Republican debate in South Carolina
Feb. 20: Nevada Democratic caucuses and South Carolina Republican primary
Feb. 23: Nevada Republican caucuses
Feb. 26: Republican debate in Houston
Feb. 27: South Carolina Democratic primary
March 1: Super Tuesday. Primaries/caucuses in several states, including Minnesota
July 18–21: Republican National Convention in Cleveland
July 25–28: Democratic National Convention in Philadelphia
Nov. 8: 2016 Election Day
Jan. 20: Inauguration of the new president
Why does it matter?
Iowa caucuses: The first test of candidates' staying power. Some will drop out after the votes are tallied.
N.H. primary: Candidates who win — or exceed expectations — here and in Iowa, will have momentum.
Super Tuesday: Multiple-state voting could provide a big boost to some candidates — and doom others.
RNC: A chance for the party's ticket to set general election themes and start making the case against the Democrats.
DNC: How strongly the nominee embraces President Obama's legacy will be a clue to fall's core messages.