Since Republicans are pretty much going extinct, will America end up being like Detroit when its 100% D?

[A Hunch]

Maybe you should redo your research.
29 states have Republican Governors
24 states voted for Mitt Romney.

It's difficult to know since the media wants us to believe that 40% of the population is independent, what percentage is Republican, Democrat, or Independent. 40% may say they are indie during a poll; 40% don't show that in their voting.

But your premise that Democrats greatly outnumber Republicans is simply false.
If California changes their electoral voting to a percentage of votes vs the current process of winner take all, can a democrat even be elected president? It's an initiative on the upcoming ballot.
- Just so you know, if that law was passed 4 years ago, there would be a Republican in the white house today. California's winner take all gave Obama 55 votes; if it was based on popular vote in CA, Obama would have had 206 electoral votes and Romney would be the US President with 236.

Note: obviously not a travel question...