This has been an unusual election season in my part of the Atlanta metro area, not just because of the time of year, but also because of the spirited and exceedingly well-funded campaign waged by hitherto unknown Democrat Jon Ossoff in what virtually everyone has regarded as a safe Republican district. Yesterday Ossoff won 48 percent of the vote in a “jungle primary” while his numerous GOP opponents split the remainder. Since no candidate won a majority, there will be a runoff between the top two vote-getters, Ossoff and Republican Karen Handel, in June.  

In my northern DeKalb County neighborhood, the Ossoff yard signs alone outnumbered all the signs I’ve seen in the last few election cycles combined. Indeed, if you took your bearings only from my part of the district, as the Washington Post did in its most recent article on the race, you’d think that Ossoff would win in a landslide. He had the money—over $8 million, more than 20 times what his closest competitor raised. He had the volunteer enthusiasm, with well-publicized, well-attended events all over the district and canvassers galore. And he had the attention of the national and local press.

Republicans, by contrast, seemed disorganized and dispirited, apparently more interested in criticizing one another and figuring out how much distance, if any, to put between themselves and the president than in reaching out to voters. I requested a yard sign from one campaign and never got a response. Let’s just say that candidate didn’t earn my vote. And after Ossoff held a well-received event on my campus, I contacted the head of the College Republicans, a group I advise, to ask if there was any interest in bringing any of the leading Republican candidates to campus. There wasn’t.

How did we get to a situation where Republicans are relieved to hold Ossoff below 50 percent and make it to June runoff in a district that they have held since 1978 and that Tom Price, now the HHS secretary, didn’t really have to break a sweat to win? If you’ll pardon my alliteration, I’ll offer three answers: trends, turnout, and Trump.

Like a lot of other relatively affluent suburban congressional districts, the sixth is a little less Republican than it used to be. It has become a bit more diverse, with increasing numbers of African-Americans, Asians, and Hispanics earning the income that enables them to afford the McMansions in the swim/tennis neighborhoods near the highly rated schools. The voters may still be more or less fiscally conservative, but they’re left cold by social issues. Indeed, in my local state-legislative race last year, all three candidates in the Republican primary professed to oppose the religious-freedom legislation that roiled the legislature in three successive sessions. They seem to want pragmatic problem-solvers, not ideologues. And that’s a game that well-spoken, intelligent Democrats can play just as well as Republicans.

Then there’s turnout, which is typically lower in special elections. This election was no exception: Ossoff’s result—slightly more than 92,000 votes, 48.1 percent of those cast—falls short of the losing Democratic numbers in two of the last three elections and is less than half of what Price garnered in three of the last four elections. But Democratic voter enthusiasm and the Ossoff campaign’s get-out-the-vote operation—crucial factors in any low-turnout election—far outpaced anything on the Republican side of the ballot. To be sure, there is the countervailing tendency for older, better educated, and more affluent voters (once upon a time very predictably Republican) to turn out more reliably than anyone else. In this election, the Democratic enthusiasm advantage fought the Republican habitual-voting advantage to a draw.

I can’t resist sharing one example of misplaced Democratic enthusiasm. My wife told me that when she was voting, a woman in front of her was disappointed that she couldn’t vote to flip the sixth; it turned out that not only was she not registered to vote, but she didn’t even live in the district. The Ossoff messaging machine generated more enthusiasm than the polls could legally accommodate.

Finally, there’s Donald J. Trump, who last November ran well behind mainstream Republicans in this district and indeed all across the Atlanta metro area. With no burning local issues (other than an interstate highway) and no charismatic local personalities, the president, for better or worse (and given the first few months of his administration, mostly worse) is at the top of everyone’s list of reasons to vote one way or the other. The energy, as it has been since November, is largely on the anti-Trump side. With the exception of the appointment of Neil Gorsuch to the Supreme Court, most of the reasons one could offer to applaud the president are of more interest inside than outside the Beltway. And they tend to be dwarfed by the colossal (if perhaps temporary) failure to win the battle over Obamacare, not to mention the manifold missteps and intemperate tweets that are, of course, magnified by an adversarial press. To be sure, Donald Trump can still seem to do no wrong among his core supporters, but not many of them live in my district.

Where does this leave us going forward? After, I hope, a brief respite, our mailbox will again be full of campaign flyers and we will have to ignore most of the calls to our home phone (yes, we still have a landline). Built for a sprint in hopes of avoiding a runoff, the Ossoff campaign will have to restock its war chest and hope that it can restoke the energy of volunteers and voters. The Karen Handel campaign will have to raise enough money to be competitive and work hard to win the support of the Republican voters who didn’t support her yesterday.

I don’t expect the Ossoff campaign to be able to outspend its rival so lavishly over the next two months, and I do expect Handel and the Republicans to work hard to disabuse voters of the moderate, pragmatic image Ossoff has so assiduously cultivated. But what happens over the next two months at both ends of Pennsylvania Avenue will matter a lot. And all I’m willing to predict there is that Donald Trump will be unpredictable.

Joseph M. Knippenberg is professor of politics at Oglethorpe University and a longtime sixth-district resident.