“Hispanics are a key swing vote, and whichever GOP candidate succeeds in winning the nomination cannot win the general election without the Hispanic vote.”
That’s not true, now. It may be the case in 20 or 30 years, but the fact is that any Republican that unifies (or gets reasonably close) the White Vote wins in a landslide.
And polls, all the polls, show that few things unify Americans more than stopping illegal immigration. Even a large portion of legal Hispanics are for more rigid enforcement, something the press doesn't like to talk about.