Nate Silver, FiveThirtyEight:
Did Trump win Hispanics in Nevada? You can be sure that Trump will tell us he did! There was a lot of nerd-fighting over who won the Hispanic vote in the Democratic caucuses in Nevada, and we suspect there will be some over the Republican caucuses as well. Indeed, the entrance poll had Trump beating Rubio 45 percent to 28 percent among Hispanics. But keep in mind that the sample size on that result is somewhere between 100 and 200 people. That means the margin of sampling error for the Hispanic subgroup is near +/- 10 percentage points (or even higher). Perhaps more importantly, just 8 percent of Republican voters were Hispanic (or 1 percent of the Nevadan Hispanic population), and they are not politically representative of the larger Hispanic community.