Chastened by Donald Trump’s surprise victory in 2016, the so-called experts are hedging their bets. This is wise. Nobody really knows what’s going to happen.

“We have polled dozens of House races over the last couple of weeks,” statistician Nate Silver said this week on The New York Times’ podcast The Daily, “Including nearly all the races that are considered toss-ups. And we have a majority of those races within one point.”

There are a dozen or so House races that Democrats are all but guaranteed to win. About 30 additional House races could go either way. Democrats only need to win about a third of these races to take the majority.

But here’s the interesting point Silver is getting at: It’s likely that those 30 races will fall definitively one way or the other, instead of splitting 50/50.

Undecided voters may overwhelmingly break one way at the very end (possibly because of some external event that neither side can control)—or the turnout model used by pollsters this cycle may have a consistent flaw that favors one side over the other.

It is amazing (and sobering) that even if one party wins all 30 races, those victories could be decided by a few thousand voters.

Just as Trump won the electoral college by virtue of eking out victories in a handful of states in the Rust Belt, Democrats may win (or lose) the House by virtue of razor-thin majorities in just enough Congressional districts.

“I think it’s worth thinking about just how different that election night would feel like,” Silver notes, “even though it just turns on a couple of points.”

(Note: This deserves a big asterisk: Thanks to congressional gerrymandering—and liberal Americans segregating themselves into densely populated cities—Democrats could win the popular vote by millions, but still fail to take the House. It is hard to imagine this scenario and call it a “close” election. Still, a few thousand voters could disproportionately impact American politics for more than 300 million Americans.)

Aside from the perks of a majority (the ability to schedule the House floor, getting gavels for oversight—not to mention subpoena power), it’s hard to discount the psychological and symbolic importance that hangs in the balance.

“ The idea that either side is going to get a majority of Americans to endorse their program seems absurd. ”

When you win, the assumption is that you did everything right. In our winner-takes-all system, it hardly matters if you win by one vote or a million.

In this age of polarization, this is truer than ever. Trump can’t claim a mandate, really. He can act like it, but he lost by 3 million votes. We are an evenly divided nation. The idea that either side is going to get a majority of Americans to endorse their program seems absurd. It may sound like putting the cart before the horse, but maybe the best you can hope for is to win the argument after you win the vote.

First, though, Democrats have to win the vote.

“Know what the difference between hitting .250 and .300 is? It’s 25 hits,” Crash Davis [Kevin Costner] rhetorically asks during one famous scene in the movie Bull Durham. “Twenty-five hits in 500 at bats is 50 points, OK? There’s six months in a season, that’s about 25 weeks. That means if you get just one extra flare a week—just one—a gorp… you get a ground ball, you get a ground ball with eyes… you get a dying quail, just one more dying quail a week… and you’re in Yankee Stadium.”

I have been wondering whether Democrats will be uncorking their own bubbly tonight. They are on deck and anxious to step up to the plate.

Unfortunately for them, the House race appears to be on the bubble.

Tuesday could be a harrowing walk across a tightrope. For the winners, it could be luck, it could be skill, or it could simply be which way the wind was blowing at that given moment. There is a thin line between winning and plummeting off the tightrope: so much comes down to whether things break your way. Does it rain on Election Day? What does Trump tweet? Did the caravan make any more progress? Should you have canvassed one extra neighborhood?

On one side is celebration, power, and popping champagne bottles. The other side is filled with stoic faces, the agony of defeat, and crushed dreams of glory. The line is thin.