Several polls have shown Clinton within striking distance in Texas, and it's not impossible that she could pull an upset there, though it's certainly more likely that Trump will win the state. Thinking about this, I was playing around with the EV calculator and realized that if the Hispanic vote becomes as reliably Democratic as the African-American vote, the Republicans will have lost the Presidency for the foreseeable future. The baseline assumption is that it becomes enough to flip Texas to D, which would also ensure FL, AZ, and NV. With those states in hand, even this is a D win (272-266):
And no, I
don't think this is going to happen this year, and it may not even be all that likely anytime soon; but if present trends continue, it might be a possibility in a few cycles.