Imagine the horror that will be felt by the right if it happens.

They assume it can’t happen. They assume Jon Ossoff, the Georgia Democrat surging in the special election to fill the Sixth Congressional District seat vacated by Health and Human Services Secretary Tom Price, will come up short, and a reliable Republican hack will ultimately win the contest. They assume that Ossoff’s momentum is nothing for than left-wing hype, and that once he has been successfully smeared by negative ads, he’ll choke instead of conquering.

What if their assumptions are wrong, and Ossoff pries this seat from Republican hands?

As Vox’s Jeff Stein notes, an Ossoff victory would scare the orange off of Donald Trump and his minions:

Georgia’s Sixth Congressional District is not one Democrats would normally have any business seriously contesting. Republicans have held the district, mostly composed of affluent suburbs north of Atlanta, with ease since 1979. Newt Gingrich and Sen. Johnny Isakson (R-GA) both held the seat. It’s gone red by about 30 points in each of the past five races, including in 2016, when Price won it in a landslide…

But though they were crushed at the local level, something in November’s returns gave Georgia’s Democrats a cause for hope. In a dramatic swing from the past four presidential elections, Trump only won the Georgia Sixth by 1.5 points. (Romney won it by 24 points.)

In particular, the seat swung hard against Trump this year as part of Hillary Clinton’s success with the educated, upscale, and suburban voters who have not historically played as large a role in the Democratic Party’s coalition. (The median income in the Georgia Sixth is $83,000, or more than double the national average, according to census data.) The extraordinary unpopularity of House Republicans’ Obamacare repeal push — which was polling at 17 percent nationally before it collapsed — is giving Democrats further reason for optimism.

“It was the second-biggest mover in the Democrats direction of any congressional district in the country,” says Geoffrey Skelley, who studies congressional elections at the University of Virginia’s Center for Politics.

Whichever way it goes, the Georgia Sixth race will not radically alter the composition of power in Washington. Right now Republicans control 238 seats to Democrats’ 194; a one-seat switch, obviously, won’t do much to loosen that majority.

But the race could transform politicians’ perception of the political headwinds, which in turn really might have serious consequences for legislating and lawmakers’ willingness to buck Trump, according to Skelley. It’s like the long-shot Scott Brown victory in 2010, which signaled coming change to terrified, vulnerable congressional Democrats.

Brown’s takeover of the Senate seat Ted Kennedy held for nearly five decades is a fitting comparison: Brown’s win demoralized the Democratic Party and signaled that the Republican Party, long assumed to be on its way to collapse in the wake of the 2008 presidential election, was alive and well. An Ossoff victory would further destabilize the GOP–and generate critical momentum for Democrats heading into other important 2017 contests, as well as the 2018 midterms.

It will be especially dispiriting for the right if Ossoff overperforms two weeks from this Tuesday:

Ossoff’s first order of business will be simply surviving the April 18 election. Georgia has what’s known as a “jungle primary” system, which means all the candidates from both parties get into the race at once.

If any one of them wins more than 50 percent of the vote on April 18, then that candidate takes the seat outright. The Associated Press recently captured Ossoff on an optimistic day, saying he hoped to win it “outright.” But if nobody clears the 50 percent threshold, then the two candidates who got the most votes — regardless of their party affiliation — advance to a second round that will be held in June.

As a result, Georgia Democrats have tried to encourage some of their five candidates for the seat to get out before it’s held. (The Atlanta Journal-Constitution writes Ossoff is “looking for the knockout blow.”) Meanwhile, the leading Republican candidate, Karen Handel, the Georgia GOP’s secretary of state, faces 11 other Republican candidates.

The crowded race has also fueled Democrats’ optimism in the face of the district’s firmly right-wing voting record. A shock poll out last week by zPolitics and Clout Research put Ossoff way ahead of a divided Republican field, with support from more than 40 percent of likely voters — a shockingly big lead, though not enough to avoid the runoff.

If Ossoff wins big and avoids a runoff, it could encourage Democrats, especially progressive Democrats, in other supposedly blood-red Congressional districts to mount insurgent campaigns against GOP House hacks in 2018. Democrats won’t be afraid of being squashed by right-wing SuperPACs and Fox News. They’ll be emboldened–and an emboldened Democratic Party is the last thing Republicans want to see.

D.R. Tucker

D. R. Tucker is a Massachusetts-based journalist who has served as the weekend contributor for the Washington Monthly since May 2014. He has also written for the Huffington Post, the Washington Spectator, the Metrowest Daily News, investigative journalist Brad Friedman's Brad Blog and environmental journalist Peter Sinclair's Climate Crocks.