It's Not So Much the Debate. It's the Days After the Debate.

[left-of-center2012]

As you prepare to watch the first primary debate Wednesday-Thursday (and the 11 to follow), let go of the notion that any single moment is going to shift the state of the race overnight. That is not to say that debates aren’t important, but real consequences tend to emerge only in the days and weeks after the debate as the news media, candidates and voters react.

It’s easy to believe the stakes are high. Tens of millions of people watch. Opponents take aim at one another. Anything can happen. Some famous debate moments include Gerald Ford’s comment that “there is no Soviet domination of Eastern Europe”; Michael Dukakis’s emotionless response on whether he would support the death penalty if his wife were raped and murdered; Ronald Reagan’s quip that “I am not going to exploit, for political purposes, my opponent’s youth and inexperience.”

In primary debates, obviously, candidates from the same party compete with one another. Party identification is not a factor in a voter’s choice, so something else needs to be. There is more movement in primaries because almost all of the candidates will eventually drop out. Voters who preferred a candidate who left the race must transfer their support to someone else.

What stops most candidates’ post-debate surge is a combination of reality and the heightened focus of media attention, which moves from narratives about an unexpected success or an increase at the polls to scrutiny of the candidate. The focus on a surging candidate may simply bring to light the underlying weaknesses of a candidacy.

Usually, only candidates who are already well known can avoid the decline that scrutiny brings.

The Democratic debates may play out differently for candidates like Joe Biden or Bernie Sanders, whom voters are unlikely to learn much about relative to, say, Kamala Harris and Pete Buttigieg. If the latter two emerge from a good performance with an initial surge in media attention and poll numbers, history suggests that a level of scrutiny will follow that matters more than a good one-liner.

https://www.nytimes.com/2019/06/26/upshot/debate-dramatic-moments-overrated.html