In the United States, presidential elections are actually held state by state. The winner in each state gets all of that state's "electoral votes," and the candidate with the most electoral votes wins the election. To win, a candidate needs to get more than 270 electoral votes.
The state with the largest number of electoral votes is California, with 55. The state with the second largest is Texas, with 38. Just those two of the fifty states control 93 electoral votes.
Those two states also happen to be the two states with the largest percentage of Hispanic and Latino population--each of them has over 38% Hispanics and Latinos.
It is hugely important for any U.S. Presidential candidate to have support among Hispanics and Latinos.
After what he said, I cannot imagine Trump winning in California or Texas, and without winning these states I can't imagine him winning the election.