I’m willing to be there are plenty of stat and polling professionals lurking on this site. I’m not one. But I thought this might be a “catch your breath” moment. There is one month until we vote in the 2018 midterms, and man, are there lots of polls! What do we make of them and what each side (and all of the candidates are doing)?
First, polls show us three things: Blips, bumps and trends. A blip is a shift in opinion that lasts for days at most. The most typical blip poll you’ll see in a midterm is after the President (regardless of party) visits a state to campaign. He shows up, the faithful turn out, and then up go the polls for a day or two — until the glow of that visit wears off and the standard environment takes back over.
We hear about bumps a lot during party convention time. Every nominee gets some kind of bump during the week of their party convention but they only last for a week or two.
Trends are polling data that stay consistent for a long time. We see these most often around issue voters, or sometimes during a primary when one candidate begins to stand out from the others and their support takes off until they win. Unlike blips and bumps, trends don’t wear off automatically — it takes a jarring event to dislodge or truncate a trend.
So what’s a blip in this season? Well, about 5 days ago Trump was in Tennessee campaigning for Marsha Blackburn. She’s been narrowly behind or tied with Phil Bredesen for this open Republican Senate seat for months. Trump shows up, and — bam! — there’s a tracking poll that shows Blackburn narrowly ahead of Bredesen. That’s a blip. When we see the next round of polling from Tennessee, I can virtually guarantee that the polls will be right back where they were before Trump showed up. There’s nothing else going that has made Bredesen less popular, or Blackburn more popular all of the sudden. It’s how blips work.
How about a bump? My vote for a bump is the rise in Republican enthusiasm that we saw when the Kavanaugh hearing started. From Super-Trumpers to Never-Trumpers, they were all in. This is their nominee and he was under attack. But guess what? He won, so now the rage is sated and the need to rally is done. How do I know it’s a bump? Because the GOP has spent the past two days trying to evolve the issue into something ongoing — so they must see that whatever they were getting out of the second set of hearings, the subsequent investigation and the vote is already dissipating.
Finally, trends: I see two great examples of these long-term voter movements this year. First is democratic motivation. Is has not dropped — not since the polls following Trump’s inauguration. It’s just flown higher and higher — even during the Kavanaugh hearings. Democrats are worried, angry and they want to vote the GOP out. That hasn’t changed in a year and half.
Another trend: There are dozens and dozens of GOP congressmen and congressional candidates across the country that have consistently polled in the lower to mid 40’s in candidate preference polls for a year or more. Some polls may have them up, many have them down, often it’s quite close — but they are always stuck sitting in a bad place for the incumbent party to be.
Obviously, as time runs near election day, any bumps and blips will be accounted for — on some level — as voters head to the polls. The question is, can any bump or blip that close to election day counter the impact of trends. That vast majority of the time, the answer is a resounding “no.”