What are we defining as a dem wave?

[Bidenworth2020]

?

[MillennialModerate]

Dems +30 in House
and No worse than GOP +1 in Senate.

[King Lear]

For me, 2018 will only be a Democratic wave if they flip the House of Representatives (and possibly the Senate). Anything less then that, especially a situation where they lose 5 or more Senate seats and fail to make double-digit House gains, will be a disaster in my book.

[Attorney General, LGC Speaker, and Former PPT Dwarven Dragon]

D+35 in the House, breaking even or better in the Senate

[JGibson]

Minimum Expectations:
Dems +36 in House.
Breaking even or at worst net -1 in Senate.

[Dr. MB]

Gaining control of both houses. No less than that.

If McCaskill/Donnelly/whoever loses and the Dems don't pickup at least Nevada and Arizona then it's not a wave.

[Roronoa D. Law]

People sure do set the bar high. The reality is a net gain of 20 seats is a wave anything over 31 is tsunami because the Democrats haven't made a net gain over 31 in the last 50 years and that ignoring the level of partisanship of today.

As for the Senate if the Democrats break even in the senate and hold all their seat. It will mean that Democrats won in 10 states that Trump won. To put that in perspective as long as Obama has been President (2010-2016) Republican have only won 10 different senate seats in states that voted for Obama in 2008. If that not wave what is?

[Badger]

Regaining control over both houses of Congress. Even a 50-50 split in the Senate will be spun as Americans still being undecided and willing to give Trump a chance, yada yada yada

[Virginiá]

People sure do set the bar high. The reality is a net gain of 20 seats is a wave anything over 31 is tsunami because the Democrats haven't made a net gain over 31 in the last 50 years and that ignoring the level of partisanship of today.

As for the Senate if the Democrats break even in the senate and hold all their seat. It will mean that Democrats won in 10 states that Trump won. To put that in perspective as long as Obama has been President (2010-2016) Republican have only won 10 different senate seats in states that voted for Obama in 2008. If that not wave what is?

I mostly agree with this. Just because the House doesn't flip doesn't mean it isn't still a wave. It just means that structural disadvantages, including gerrymandering, were enough to blunt the wave. If Democrats won 23 seats, how is that fundamentally different than winning 24? Or 25?

I'm not 100% sure on the Senate. The map is very unfavorable, after all. I think having like -1 net loss but taking over the House still qualifies as a wave.

In the end, I think the House PV matters the most. If Democrats win the House PV by 8%, that qualifies as a wave in my book, even if the seat turnover is lackluster. Those are wave numbers, and if the seat share doesn't reflect it, it's just a reminder of how biased the system is against population clustering / city folk.

[Calthrina950]

I would define a wave as one where the Democrats take control of the House and hold even, or make gains, in the Senate. If they fail to win the House, then that is not a wave for me.

[Holy Unifying Centrist]

Regaining control over both houses of Congress. Even a 50-50 split in the Senate will be spun as Americans still being undecided and willing to give Trump a chance, yada yada yada

Is that how people saw 2010?

[Pericles]

Democratic House. That's it. 218=wave, 217=disappointing failure.

[Attorney General, LGC Speaker, and Former PPT Dwarven Dragon]

Regaining control over both houses of Congress. Even a 50-50 split in the Senate will be spun as Americans still being undecided and willing to give Trump a chance, yada yada yada

Is that how people saw 2010?

If that was a serious question, No. Obama himself called the 2010 midterms a shellacking.

[politicallefty]

Democrats must win the House, probably with a few seats to spare (I'm thinking D+30). Considering the variable geography of seats up, I don't think the Senate is really relevant in terms of measuring a wave. As to the true depth of a wave, I would look at the Governors races and state legislatures.

Not to get too much into terminology, but I'd say a tsunami is closer to at least D+45 or so in the House, outright control of the Senate, and 2010-style losses in reverse in the state legislatures.

[BuckeyeNut]

Regaining control over both houses of Congress. Even a 50-50 split in the Senate will be spun as Americans still being undecided and willing to give Trump a chance, yada yada yada

Don’t let idiotic and unrealistic pundits set your bar, Badger.

[adrac]

The House flips, less than 2 GOP pick-ups in the Senate, Republicans lose governorships in important swing states.

I'd like to reinforce that state-level outcomes are important here too. The gubernatorial and state legislature elections were much more crucial to 2010's status as a wave than whether or not the Republicans managed to take the Senate.

[Ronnie]

I think a wave would be narrowly winning the house and losing no more than two net seats in the senate.  A tsunami would involve winning both chambers, the house comfortably.

[GeorgiaModerate]

I like the definitions 538 came up with (https://fivethirtyeight.com/features/what-happened-to-the-democratic-wave/):

anti-wave (Democrats lose House seats)

trickle (Democrats gain 0 to 10)

swell (Democrats gain 11 to 24)

wave (Democrats gain 25 to 35)

flood (35 to 50)

tsunami (50+)

[Adam Griffin]

A Dem national congressional PV greater than that of the GOP's in both 2010 and 2014 (i.e. 7-point win or more).

[Orser67]

Imo, a net gain of 20 seats in the House is a decent cut-off. I realize that it might seem odd for the Dems to win a "wave election" and not take control of both houses, but an election can be both a wave and a disappointment for one party depending on expectations.

[Hammy]

Imo, a net gain of 20 seats in the House is a decent cut-off. I realize that it might seem odd for the Dems to win a "wave election" and not take control of both houses, but an election can be both a wave and a disappointment for one party depending on expectations.

It would make sense this year though, there simply aren't enough Republicans up for reelection in competitive states this year.

[pbrower2a]

Senate and House flip D. Democrats must hold onto some Senate seats that would be lost in a normal election, as there has yet to be a 'reverse wave' of 2006, and this is normally the year in which such happens. There are few opportunities. 

[Torrain]

I like the definitions 538 came up with (https://fivethirtyeight.com/features/what-happened-to-the-democratic-wave/):

anti-wave (Democrats lose House seats)

trickle (Democrats gain 0 to 10)

swell (Democrats gain 11 to 24)

wave (Democrats gain 25 to 35)

flood (35 to 50)

tsunami (50+)

This, measuring the wave on a spectrum

[Person Man]

I like the definitions 538 came up with (https://fivethirtyeight.com/features/what-happened-to-the-democratic-wave/):

anti-wave (Democrats lose House seats)

trickle (Democrats gain 0 to 10)

swell (Democrats gain 11 to 24)

wave (Democrats gain 25 to 35)

flood (35 to 50)

tsunami (50+)

This, measuring the wave on a spectrum

I would say one dozen to two dozen house seats is a "status quo" election.