There is absolutely no indication that Texas is becoming a swing state.
B-b-b-but muh demographics 
Here's my map which assumes a close 50/50 election:
I bet you anything Maine doesn't vote to the right of NH.
Why? Maine - unlike NH - does not border the bluest of blue states (NH-02 is actually pretty competitive).
This is a lie. Maine borders NH, of course.
In all seriousness, what does NH bordering MA have anything to do with it becoming more liberal? The most Republican part of the state is the Boston suburbs.
