Time is the most important factor, especially for Hispanics. That group is only going to get wealthier and more economically stable in future generations, which most likely means a more conservative impulse.
There will be some GOP gains with time and economic growth, but it probably won't be dramatic. Consider New Mexico, where the Hispanic community has deep roots and includes relatively few recent immigrants. Obama still got 65% of Hispanic voters there in 2012 based on exit polls. Of course, people from Hispanic families that have been in NM for 100 years might not identify as Hispanic for the exit poll, but Obama also got 64% of the Catholic vote.
Now if they could find a way to win both 35% of Hispanic voters and 65% of white voters, that would be enough to win well into the 2020's. This is why I think SoCon candidates will make a comeback, but this time they will be Catholic rather than Evangelical.
Yeah but NM is more of a state where people vote for the person and not the party. The Governors Mansion in NM has flipped back to each party back and forth in each of the last 2 and a half decades. It really doesn't matter if Hispanics have been there for 100 years NM doesn't vote like a TX, or a CA. Keep in mind Romney didn't even campaign in NM and still got 44% of the vote there.
Keep in mind too that NM hasn't gained an electoral vote in how many years? Its not growing like other states are in the Southwest US.