Though this has sometimes proven to be true, what's even more true is that not voting at all often leads to much more liberal governance. It must be again noted, that if as many people had voted for Romney, as had voted for McCain, Romney would be president now. You can say what you want about Romney, he would have been far far better than a second Obama term.
Shoulda, woulda, coulda is for children and liberals.
Reality is that conservatives aren't going to vote for the liberal republican any more.
/johnny