The evidence of a Democratic wave that would lead to majority control of the House has mainly consisted of theoretical speculation and braggadocio. With the national election just a few days away and other evidence conspicuously absent, a general consensus has formed that Democrats will remain in the minority in the lower chamber of Congress for at least another two years. Roll Call’s Nathan Gonzales reports that the most recent data suggests that Democrats will gain 13 seats at most — far short of the 30 needed to flip the House:

A Democratic majority in the House has always been a stretch. But now that Donald Trump is closing in on Hillary Clinton at the top of the ticket, Democratic hopes of making Nancy Pelosi Speaker of the House once again have all but evaporated.

There is no question House Republicans have vulnerabilities and will lose seats, they just won’t lose the 30 that Democrats need for a majority, even with Donald Trump’s volatility at the top of the ticket.

A couple dozen races look like they are within the margin of error, but there isn’t any evidence to suggest they will break disproportionately toward Democrats. The party looks likely to gain eight to 13 seats.

The Washington Post’s Amber Phillips and Aaron Blake put the spread wider — as many as 20, but perhaps as few as five:

According to the just-updated Fix House race ratings, just 49 out of 435 congressional districts are competitive. Democrats haven’t been able to stretch the map to give themselves many additional opportunities — with a few notable exceptions — and races that are on the board haven’t really moved in Democrats’ direction much in recent weeks.

That’s a testament to Republicans hanging tough in a tricky political environment for them. They are defending 26 districts that President Obama won not just once but twice. And Democrats got plenty excited when it looked like the Trump implosion was arriving in mid-October. And yet it doesn’t seem like Democrats’ attempts to cast down-ballot Republicans as mini-Trumps is resonating with as many voters as they would have hoped.

In order to win the majority right now, Democrats would have to take 36 of the 49 competitive districts. That would translate to winning every “lean Democratic” district and every “toss-up” district, as well as 9 out of 22 districts we currently rate as “lean Republican.”

That said, even if Democrats take half of the “toss-ups,” they’ll have gained 13 seats and cut the GOP majority almost in half.

There are a couple of reasons to bet on the low side for Tuesday, and almost none to bet on the high side. First, polling on the generic Congressional ballot has tightened up over the last couple of weeks. The RealClearPolitics average had Democrats up 6.2 points on October 14th, but now shows them leading by only 3.3 points. FiveThirtyEight has the polling even closer after its weighting for reliability — just a 2.8-point lead for Democrats, and nearly no change in that gap for four months. Given that this polling tends to overstate impact for Democrats, it looks as though the electorate is almost evenly split. In order for Democrats to hit a wave that would lead to a significant shift, they would need to see leads approaching or reaching double digits, and that has just not materialized at all in this cycle.

Second, Democratic hopes in the House depend on enthusiasm and turnout. Not only is enthusiasm down overall in this election, it’s even more dampened among key Democratic demos, especially African-American voters. Some of that might be reflected in the generic ballot polls, but it’s almost certainly not entirely built into those numbers, either. If Democrats don’t turn out in the kind of numbers that are normally seen in presidential election cycles, then the 2.8-point lead is going to look far too optimistic. They may be lucky to get eight seats under those circumstances.

The long-term consequence of falling short in this cycle is the certainty of remaining in the minority until at least 2020, and perhaps longer than that. Republicans control a record number of state legislatures (at least for now), and if they continue that dominance, then they will control the redistricting process again after the 2020 census. Republicans could keep the gavel a long time — if they manage to avoid screwing it up.