Will the polls hold up?

It will be interesting to see if the actual votes reflect the polls. Caucuses aren't really voting in elections, but the result of an hours long process. So they probably only attract the passionately committed. That aside, it could well be that it is one thing for those enraged at Wall Street or those enraged at immigrants to tell a pollster that they support Sanders or Trump, but it may be quite different to actually cast a vote for them.