It’s the duty of every pundit to note that entrance polls are to be treated with care and often end up not being predictive. Still, reading the tea leaves can highlight interesting trends. One set of statistics makes evident a genuine problem for Clinton, if the numbers hold up. Non-whites are supposed to be Clinton’s firewall, but in Nevada, at least according to the CNN entrance polls, Sanders is leading with Latinos 54 percent to 43 percent. The same poll has Clinton winning non-whites 52 percent to 46 percent, which means that if Clinton has a firewall, it is among African-Americans. That might be enough to help Clinton win the caucus and maybe even the nomination, but it means she has less breathing room than we thought even a few days ago.