What exactly is a "wave election?"

  • 21 June 2018
  • NormanL

There's been a lot of talk about the November elections being a "Democratic wave" that will swamp the GOP and hobble the president's agenda. We'll see what actual voters have to say about that. But for all the talk about "wave election," what exactly does the term mean?

The folks at Ballotpedia have crunched the numbers, looking at a 100 years of state and federal election results. The result is  a study that seeks to define what qualifies as a real "wave election," and what doesn't. For political junkies, and for anyone interested in putting elections in historical perspective, it's a useful report. Here's a sample:

We define wave elections as the 20 percent of elections where the president's party lost the most seats during the last 100 years (50 election cycles).

While there is not an agreed-upon definition of waves in political science, a number of scholars and journalists have tried to define the concept focusing mostly on the House of Representatives. Most frequently, political scientists will set a specific seat gain as being necessary for an election to qualify as a wave. For example, Stu Rothenberg and Al Turchfarber classify elections as waves if a party gains at least 20 seats. Rothenberg’s definition also requires that the other party have minimal losses in the election.

Jacob Smith, an author of this report, previously defined a wave election as “a congressional election that (1) produces the potential for a political party to significantly affect the political status quo as (2) the result of a substantial increase in seats for that party.” Under this definition, elections are compared to recent previous years in terms of both seat swing and seat gain.

In most cases, these definitions produce similar results to the definition presented here, although the 20-seat-swing standard means that many historical elections will be counted as waves given the high electoral volatility of that time period.

So what's all this mean for the November elections? For there to be a real "wave," the numbers have to break like this:

* Democrats would have to gain 51 House seats

* Plus seven Senate seats

* Plus seven governorships

And pick-up almost 500 state legislative seats.

That's a very, very tall order. Then again, a true "wave election"should be hard to achieve -- and thus, rare. That's not to say those politicians who lose won't feel as though they have been swamped. But this sort of definition helps ground all the chatter, and the spin, in hard data.