As witnessed by the fact that Obama's totals from 2008 to 2012 dropped while Romney was unable to match McCain's totals in 2008. Those disaffected Obama voters largely didn't vote.
The GOP still has their head stuck in 2000 as to running an election. People get sick of phone calls and TV attack ads. You have to come up with new ways to reach potential voters, engage them and sway them to your side. Rove is a direct mail guy. And it shows.
Too bad there wasn't a "none-of-the-above" option - it would have probably won.
Romney left a lot of votes on the table with his campaign which seemed to alternate between two themes: "I not Obama" and "Me, too, just not as much". When Romney spoke on conservative themes, he seemed as uncomfortable as he would have been if he had been asked to give a speech in Icelandic - he was speaking a language foreign to him.