"Facts are Stupid Things"

or so Ronald Reagan once allegedly opined on the road to sainthood & senescence....

But for sheer overwhelming stupidity, you can't beat last week's presidential debate, and you have to likely go back to 1980 to find a pairing two more unpopular presidential candidates.
That debate has entered Reagan Mythology as a defining moment in Saint Ron's meandering Path to Power, people forget though that the polls up to the beginning of October described a tenuous lead for then President Carter. Reagan needed that debate badly to disperse however temporarily his well earned rep as a low info politician who was quick on the trigger.
Accordingly his campaign caved in to almost all President Carter's pre-debate demands all in a desperate effort to get the incumbent in the room in time to make an impact on the election. Carter for his part agreed to the debate fatally late in the campaign so when Reagan vaulted that low bar set for him that was a signal for the late-deciders to desert the democrats in epic droves.
Carter made the mistake of thinking he could tease Reagan into saying something stupid , Reagan could always do that on his own he proved however remarkably difficult to bait when push  came to shove.
Gerald Pomper's seminal election summary indicated that the subsequent GOP Landslide was no validation of conservative ideology, rather it was a desperate search for a President who could take control of events.

Back in 1980 It took about a week for that to happen, just as it has taken a week for Trump's terrible first debate performance to sink in with the electorate and wipe out all the gains he made in September.
If you are a democrat, do not rejoice in this there are more debates to come and like Reagan, the bar is set lower for Trump than it is for Clinton.
And based on what happened in 1980, voters can change their minds twice in a short period of time....with no ill effects.
Remember it is All About Leadership, focus on that and you win.