Why did Mitt Romney...

...lose the 2012 election to President Obama? Books will be written on that topic.

In the meantime, the Boston Globe has an excellent piece on the difference in the two campaigns. In a nutshell, the president's organization was just far superior.

I would add two more thoughts, for starters:

(1) It's just really, really hard to beat an incumbent. Really. (Even George W. Bush won reelection in 2004.)

And,

(2) Unfortunately for Gov. Romney, the economy was improving throughout 2012, albeit slowly.

Those two factors alone made a Romney victory in 2012 a long-shot.