Voters in Georgia's Sixth Congressional District will have 18 candidates to choose from Tuesday when they decide who should fill the seat vacated by former Representative Tom Price, a Republican who was tapped to become President Trump's health and human services secretary.

But none have earned more press, or raised more money, than Jon Ossoff, 30, a Democrat and documentary filmmaker who bills his campaign as a way to "Make Trump Furious."

Now, in one of the first political tests of the Trump presidency, the question is whether he can turn anti-Trump anger and energy into enough votes to send him to Congress from a wealthy suburban district that has not sent a Democrat to Washington in decades.

Here are some key questions about Tuesday's election.

Can Mr. Ossoff land a knockout in Round 1?

The top two vote-getters on the crowded ballot will advance to a June 20 runoff — unless one of them earns more than 50 percent of the vote.

Mr. Ossoff, more than his Republican opponents, may need a knockout blow of 50 percent plus one. That would allow Democrats to avoid a long and costly slog toward a runoff when a Republican candidate is likely to be heavily favored in a one-to-one matchup.

Mr. Ossoff has raised more than $8.3 million, much of it from out-of-state donors, helping to fuel an energized ground game rife with local volunteers. But Republicans have countered with attack ads against him. One features images of Osama bin Laden and argues that Mr. Ossoff is untrustworthy because his documentary company produced films for Al Jazeera, the Qatari TV news network.

Many Republicans feel confident that with one Republican running in June instead of 11 now, the district would elect whoever survived the primary in a runoff against Mr. Ossoff.

What kind of Republican candidate are voters looking for?

Some of the Republicans vying to replace Mr. Price have embraced Mr. Trump's rhetoric and positions. One of them is Bob Gray, a business executive and former City Council member in Johns Creek, Ga., who says he will be a "willing partner" of the president.

But Mr. Gray's experience shows how complicated and fractured Republican politics have become. He was endorsed by the Club for Growth, the small-government group. But he has since been attacked over that endorsement by a pro-Trump group called the 45 Committee, which, in a recent ad, called the Club for Growth a "D.C. special interest group" that was propping up "Bob Gray's failing campaign."

The Club for Growth opposed the failed effort that Mr. Trump favored to replace the Affordable Care Act on the grounds that it was not conservative enough.

Other strong Republican contenders include Karen Handel, the former Georgia secretary of state; and two former state senators, Judson Hill and Dan Moody.

Ms. Handel has called herself "an enthusiastic supporter" of Mr. Trump, but her enthusiasm has been more muted than that of Mr. Gray, who, in one ad, portrays himself standing in a swamp, draining it in chest waders.

Many observers believe that a more mainstream Republican like Ms. Handel would be the most formidable runoff opponent to Mr. Ossoff, offering a safe harbor for Republicans who are put off by Mr. Trump's style or wary that his evolving policy positions will stray too far from Republican orthodoxy.

Which voters will turn out?

And at what strength?

Early results indicate that nearly 55,000 people in the district turned out in the early voting period that ended on April 14. The New York Times's Nate Cohn has estimated that about 57 percent of those early voters would have voted for Hillary Clinton, but he also noted that many reliable Republican voters would not be casting their ballots until Election Day.

Kerwin Swint, a political-science professor at Kennesaw State University, said that if Mr. Ossoff wants to score a surprise knockout, young voters will be crucial. "Young voters in that district are really excited by him," Mr. Swint said. "He's like a Bernie Sanders-type Democrat — the future."

More broadly, Mr. Swint said he would be watching the turnout in the northern areas of the district, which tend to be more conservative, to gauge the prospects of Republicans, and the southern part, which is more diverse and closer to Atlanta, to gauge the prospects of Democrats.

Will minority voters show up for the Democrat?

The race thus far has been framed as a test of Mr. Trump's popularity among white suburbanites, and of the gains the anti-Trump movement might be making among such voters.But the district, though about 70 percent white, also has significant minority populations. Blacks make up about 13 percent of the population, Asians about 11 percent and Hispanics about 13 percent, according to census figures.

People are going to be watching to see if minority voters turn out at a rate that's even remotely proportional to their percentage of the population," said Andra Gillespie, a political-science professor at Emory University.

The Democratic Congressional Campaign Committee has sunk a six-figure sum into ads on Atlanta radio stations targeting African-American voters.

"Remember what happened the last time people stayed home," the actor Samuel L. Jackson says in one ad. "We got stuck with Trump. We have to channel the great vengeance and furious anger we have for this administration into votes at the ballot box."

How will each party spin the results?What happens in Georgia on Tuesday night is sure to resonate nationally. That poses opportunities and risks for both parties.

Last week, the Republican Ron Estes won a special election in Kansas' Fourth Congressional District, filling the seat previously held by Mike Pompeo, Mr. Trump's new C.I.A. director. The losing Democrat, James Thompson, was nonetheless able to reduce the Republican margin of victory in the district to 7 percentage points from 31 points in 2016.

Mr. Trump, in a Twitter post Sunday night, criticized the news media for its focus on both races and insinuated that reporters were overemphasizing anti-Trump sentiment.

The recent Kansas election (Congress) was a really big media event, until the Republicans won. Now they play the same game with Georgia-BAD!— Donald J. Trump (@realDonaldTrump) April 17, 2017For Republicans, a decisive victory, whether it comes now or in June, would throw some cold water on the notion that Mr. Trump has made congressional candidates more vulnerable in the midterm elections next year.

If Mr. Ossoff pulls out a victory, Mr. Swint said, Democrats will probably use it to show Mr. Trump's weakness — "that this guy is a lame duck already," he said.

But Mr. Swint is among many here who see a runoff as a more likely outcome. And he sees a danger for Mr. Ossoff even if he finishes first on Tuesday.

If Mr. Ossoff makes the runoff but underperforms — garnering, Mr. Swint said, about 40 percent of the vote or less — Democrats may decide to stop pouring money into what they perceive to be an uphill battle.

New York Times, April 18,201

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