The Electoral College Looking Forward
First off, Bush got 286 EVs in 2004. Based on projections by the census dept. begun in 1995, if a GOP wins the same states as Bush did in 2004 they will get 287 EVs in 2012-2030. That is an interesting number b/c it shows that neither party will gain or lose a huge voting block as a result of changing population.
The next thing to look at is how solid the numbers are. In the 2004 election, the closest states were Ohio, New Mexico, Wisconsin, Nevada, and New Hampshire. It would seem logical that these 5 states will be the most likely states to change parties in the next few elections. Currently they are worth 44 EVs total, of which Bush got 30 (Ohio, New Mexico and Nevada) and Kerry got the other 14. Over the next 20 years the only change here will be that Ohio will fall to 19 EVs in 2010 and to 18 in 2020. The other 4 states will stay the same.
This basically means that from our perspective the electoral map will not change for the next 25 years. The GOP wins when it wins all the states it is supposed to win plus Ohio and one other "swing state". The dems win if they win OH or all the other swing states.
From what I can see, Virginia is probably one of the only solid Red states that seems to be "turning blue". If that is the case, the GOP should still be in good shape since they can win without Virginia (287-13=274). Of course they would still need to win all the other states Bush won in '04, which is never going to be a guarantee. It appears, if Virginia is truly becoming a dem winnable state, that the electoral strategy may become the GOP needing to win either OH or VA to win with the dems needing to carry both to win.
At the end of the day, there is really no way of knowing what the future will hold for any particular state regarding its political leanings. The only thing we can tell is that if states do no change their politics; the electoral strategy for both parties will not change much either.