ANALYSIS: Trump faces early referendum in Georgia congressional race

PHOTO: Democratic U.S. House of Representatives candidate Jon Ossoff greets volunteers at a campaign office in Chamblee, Georgia, April 13, 2017 | President Donald J. Trump in the East Room of the White House in Washington, March 28, 2017.
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WATCH High stakes for congressional election in Georgia

Now is not the time and a certain Georgia district hardly the place that President Trump would choose for a referendum on his performance or his political coattails.

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But there's no choice.

A special election to fill an open House seat is happening today in a suburban Atlanta district that, although Republican, went for Trump in November by the slimmest of margins.

The national implications of the race have only grown in recent days. Both Republicans and Democrats have poured resources and attention into the election in hopes of sending a message that will reverberate to any other one-off special elections and beyond to 2018.

The momentum has been behind Democrat Jon Ossoff, who is facing down 11 Republicans in a field of 18, although the chance of any candidate – much less a Democrat in a Republican district – avoiding a runoff by clearing 50 percent in the first round seems remote.

With Ossoff expected to be the top vote-getter today, however, an irony has emerged. Trump exploited deep divisions in the Republican Party to power his rise to the nomination and the presidency. Now, though, he needs that same Republican Party to put aside its divisions long enough to save itself a House seat.

The White House's messaging on the race is aimed at holding down Ossoff without endorsing any of the Republican candidates vying to defeat him. In a robocall going out to voters in the district, the president tries to link the young Democratic candidate to House Minority Leader Nancy Pelosi and warns of dire consequences should he win.

“If you don’t vote tomorrow, Ossoff will raise your taxes, destroy your healthcare, and flood our country with illegal immigrants,” Trump said.

If the president's message seems grave, he has reason to sound alarms.

Ossoff is only 30 years old, and is a former congressional staffer who doesn’t even live in the district. He became shockingly competitive almost overnight in a district previously represented by Health and Human Services Secretary Tom Price and former House Speaker Newt Gingrich.

The district has sent a Republican to Congress since 1979 – longer than Ossoff has been alive. Price cruised to reelection Nov. 8, but Trump beat Hillary Clinton there by less than two percentage points on that same day. In contrast, Republican presidential nominee Mitt Romney won the district by a whopping 23 points four years earlier.

This is a Republican-heavy, upscale suburb that was skeptical of Trump before he became president, back when few thought he could actually win against Clinton.

Given the tumult of Trump’s first 89 days in office, few would argue he’s in a stronger position now than in November. That’s the message other Republicans are likely to draw from this race, as a snapshot of the president’s political standing, in one tiny swath of a state he carried.

If Ossoff wins on Tuesday or in a June 20 runoff, it will boost the momentum of Democrats in fundraising, candidate recruitment, and energy going into the midterm election year.

Possibly more problematic for Trump, however, is how a loss in this race could affect his ability to govern in an environment where he needs his own party to fear as well as love him.