Kamala Harris's Debate Bounce Is Fading (by FiveThirtyEight) [View all]

[Skya Rhen]

We’ve documented for years how polls tend to rise and fall — in what are often fairly predictable patterns — after events like debates and conventions. In general, what suddenly goes up in polls tends to gradually come back down after a matter of a few weeks. Conventions typically produce polling swings of 4 to 6 percentage points toward the party that just nominated its candidate, for instance — but the polls usually revert back to about where they were before after a few weeks.


We’ve also repeatedly seen this pattern after various Democrats declared for the race this year. Joe Biden, Bernie Sanders, Kamala Harris and even Beto O’Rourke all got noticeable bounces when they officially declared for the presidency, only to fall back to their pre-declaration averages later on.


It looks as though something like this is happening again following the first Democratic debate last month. If you look at the RealClearPolitics average:

Biden has rebounded to 28.4 percentage points from a low of 26.0 percentage points just after the debate. He was at 32.1 percent before the debate, so he’s regained about two-fifths of what he lost. Harris has fallen to 12.2 percentage points from a peak of 15.2 percentage points. She was at 7.0 percent before the debate, so she’s lost about a third of what she’d gained.




https://fivethirtyeight.com/features/harriss-debate-bounce-is-fading/?yptr=yahoo