Donald Trump: I’d consider trying to overturn Supreme Court marriage decision

Welcome to Trail Guide, your host through the wilds of the 2016 presidential campaign. It’s Sunday, Jan. 31, and here’s what we’re talking about:

  • Donald Trump says he disagrees with the Supreme Court’s decision allowing same-sex marriage and would try to overturn it
  • Democrats agree to another debate -- a few days before the New Hampshire primary
  • Hillary Clinton says emails found on her private server and deemed to be classified should be released
  • On the eve of the Iowa caucuses, The Times’ Mark Z. Barabak explains how they work and why they matter so much
  • Candidates barnstorm Iowa -- Trump inviting kids onto his private jet and Bernie Sanders singing with Vampire Weekend -- as they woo voters down to the wire
  • Iowa’s most deeply conservative and strongly liberal pockets are united in one way: a sense of dread. What voters there are telling us