There's zero evidence a 'red wave' is forming in 2018

And so, when Democrats -- and non-partisan political analysts -- suggest that all signs point to a blue wave in the 2018 midterm elections in 56 days time, Trump has a ready retort: "Red Wave."

"A Blue Wave means Crime and Open Borders. A Red Wave means Safety and Strength!" Trump tweeted on August 21.

He went with the simple "RED WAVE" in a tweet on August 8. And following the California primary in early June, Trump tweeted this: "Great night for Republicans! Congratulations to John Cox on a really big number in California. He can win. Even Fake News CNN said the Trump impact was really big, much bigger than they ever thought possible. So much for the big Blue Wave, it may be a big Red Wave. Working hard!"

As Trump's 2016 election victory proved, anything is possible in campaigns. But history suggests that the idea of a red wave -- given everything we know about this election cycle so far -- is incredibly far-fetched.

Let's go through a few of the historical hurdles Trump has to bypass to make the "Red Wave" a thing:

Since the Civil War(!) the party that controls the White House has lost House seats in 35 out of 38 midterm elections. The three elections in which the president's party won seats in a midterm were 1934 (Great Depression), 1998 (Bill Clinton impeachment) and 2002 (aftermath of Sept. 11 terrorist attacks). Those were all massive societal and cultural happenings.Since 1946, the average seat loss for a president's party when that president's job approval rating is under 50% is 36 seats. In the latest CNN-SSRS poll, Trump's job approval is at 36%. That's similar to George W. Bush's 38% approval in 2006 when his party lost 30 House seats -- and control of the chamber.Since direct election of senators (in 1913), there have been 26 midterm elections. The president's party has lost Senate seats in 19 of them, per Charlie Cook.

That's a whole lot of history. And it all points in the same direction -- toward major seat losses in the House and a less certain outcome in the Senate where the national map (and raw numbers) are heavily tilted in Republicans' favor this year. (There are 26 Democratic Senate seats up in November as compared to just 9 Republican seats; in 10 of those 26 Democratic seats, Trump carried the state in 2016.)

On the Trump side of the equation, there's a lot less history. Let's take a look at what happened in those three anomalous years -- 1934, 1998 and 2002 -- in which the president's party picked up House seats.

1934: Democrats gain 9 seats1998: Democrats gain 4 seats2002: Republicans gain 8 seats

None of those would fit anyone's definition of a wave election. Single-digit gains in a body of 435 seats is marginal -- at best. And remember that those single digit gains for the president's party came in election cycles defined by cataclysmic events.

For Trump's "red wave" to materialize, history suggests he needs an election-altering event -- like in 1934, 1998 and 2002. Short of that, history is very, very likely to repeat itself. And that means Republicans' House majority is in deep trouble.