Republican bench

I heard some commentator note that the Republicans have a "deeper bench" than the Democrats, when it come to presidential prospects, and I've found myself thinking about it ever since.  That may be true, when you consider personalities currently in the public eye - Nikki Haley, Chris Christie, Marco Rubio, etc.  But I think the Dems often pull someone charismatic out of obscurity, as Obama epitomizes. So I'm not too worried, but I will be so interested to see what happens in 4 years.