The 332 electoral votes that Obama won on Nov. 6 not only affirmed that edge but also raised the question of whether Democrats were in the midst of the sort of electoral college stranglehold that Republicans enjoyed during the 1980s. (Ronald Reagan won 500+ electoral votes twice; George H.W. Bush won 426 in 1988.)
This chart -- put together by Brad DeLong, an economist at Cal-Berkley -- shows just how firm a grip Democrats have on the electoral map. If the 2016 Democratic nominee carried only the states that President Obama won by 4.5 points or more last month, he/she would end up with 272 electoral votes and a victory.
Now, things can change quickly in electoral politics. In 2004, no one was talking about Virginia and North Carolina as swing states but they quite clearly are just that now. And, it's an open question as to whether the next Democratic presidential nominee can build the same coalition -- blacks, Hispanics, young people etc -- that President Obama was able to do in both 2008 and 2012.
Those caveats aside, the electoral college math looks decidedly daunting for Republicans as they begin to prepare for 2016 and beyond.