I will take a simple approach. There are Democrats and Republicans. No argument there. Let's look at the Clinton's for a moment. Just think about them for a second......... OK, time is up. Now suppose, just suppose the Nixon's are alive. Pat is 64, Dick is 67. They want to get back in the White House but Dick knows he can't get a third term. So he runs his wife. (I guess you know where I'm going with this but hang on). As you know the Clinton's had the most scandal ridden administration of all time.
But wait, the Nixon's administration wasn't exactly Snow White. Democrats could certainly put forth a strong case about the scandals and corruption of his administration, although, he did have enough integrity to resign, rather then be impeached, unlike some people I know. That said, if he were running today (sorry, I meant his wife) with the rest of the Republican field there would be no way in hell I or the vast majority of Republicans would vote for him (I mean her).
He was exposed for what he is, and for his actions. Also, the Media would have a field day putting Nixon through a meat grinder while the Clinton's gets a free ride. I happen to like Nixon, but there's no way he's going back to the oval office.
So, why in the world as a Democrat would you want Billiary back in the White House? An impeached, disbarred, x-president! A disgrace to the nation! The butt of late night talk show jokes! Baggage that a freight train couldn't handle! This is the best that they could come up with? Think about what will happen if they get in. We will regurgitate all the Clinton scandals. Not to mention, start a slew of new ones. Sounds appealing doesn't it. The buzz word in politics now is change. 'We want change'. Where in the hell is the change in this? Tell me where I'm going wrong. Don't believe me? Punch in "Clinton scandals" on Google. Your computer will blow a gasket!