The transition from the 2018 midterm elections to the 2020 congressional election season will be completed on Tuesday, with things right where they were 10 months ago: the GOP trying desperately to save a once-safely-Republican seat anchored in rapidly shifting suburbs. Recent polls have shown the race in North Carolina’s 9th District, between Democrat Dan McCready and Republican Dan Bishop, to be a coin flip, and both President Donald Trump and Vice President Mike Pence are visiting on Monday to rally the base.

In the initial vote last November, Republican Mark Harris appeared to have narrowly defeated McCready, but the state refused to certify the tally, as certain ballot-tampering hijinks, including illegal ballot-collection tactics allegedly employed by operatives linked to the Harris campaign, called into question the integrity of the results. After four days of testimony in February in which the scheme was fleshed out, a very rare revote was called.

Harris, citing medical issues, chose not to run again. (Embarrassment also may have played a factor.) The previous holder of the seat, Robert Pittenger, had lost to Harris by fewer than 900 votes in the 2018 Republican primary (thanks in part to a reported “surge of absentee-by-mail ballots” in Harris’ favor), but he did not enter the special primary. So the nomination went to Bishop, a state legislator and Trump enthusiast.

The outcome in this district, which has a Cook Partisan Voter Index of R+8, will serve as an early data point for how the 2020 elections might play out. It’s a test case to see whether the factors that fueled Democrats to a 40-seat House gain in the 2018 midterms have retained their potency, or whether eight months under a Democratic House, against the backdrop of a Democratic presidential primary, have tempered some of the anti-Trump anger in a district that Republicans have held since 1963.

The outcome in this district will serve as an early data point for how the 2020 elections might play out.

The 9th District, which spans from Charlotte and its southeastern suburbs along the state’s southern border toward Fayetteville and Elizabethtown, offers another example of the gerrymander rot that Democrats took such advantage of last cycle: Its immediate suburban areas, once the bedrock of the Republican coalition, have trended blue under Trump as its more rural areas have turned sharply red.

In the district’s portion of Mecklenburg County—i.e., Charlotte—McCready won 54 percent of the vote in 2018, outperforming Hillary Clinton’s 2016 performance by 8 percentage points and 2,500 raw votes. McCready also hopes to do better in Union County immediately to Mecklenburg’s east—eloquently described in the Hill as “full of poultry farms and precincts dominated by white voters”—where he lost by 20 percentage points in 2018. McCready is the sort of purple-district congressional candidate whom the Democratic Congressional Campaign Committee grows in a lab these days: a 36-year-old centrist Marine turned management consultant and entrepreneur whose campaign focuses strictly on kitchen-table issues while rejecting bold, progressive visions for “Medicare for All” and a Green New Deal.

It will shock you to learn, however, that despite McCready’s efforts to distance himself from the left flank of the Democratic Party, Republicans have nevertheless portrayed this military-groomed McKinsey suit as ascendant in the revolutionary vanguard. In that sense, McCready is serving as the first subject of the GOP’s Great Congressional Villain Switch-Out of 2019: Republicans aren’t only tying Democratic congressional candidates to House Speaker Nancy Pelosi anymore. Now they’re tying them to the “Squad.”

In his first campaign ad this spring, “Clowns,” Bishop appeared before a slew of swaying blowup clowns featuring the visages of prominent, evil Democrats. Watch, at the :05 mark, as the face of Minnesota Rep. Ilhan Omar slides into the close-up of McCready. The only other close-up is of New York Rep. Alexandria Ocasio-Cortez. Meanwhile, yesterday’s news—Clown Nancy Pelosi—can only look on from the background.

Bishop, a state senator who in 2016 sponsored North Carolina’s infamous “bathroom bill,” spoke at the North Carolina rally in July during which Trump’s mention of Omar prompted the crowd to chant “Send her back!” Trump also described McCready during that rally as an “ultraliberal” who “likes open borders” and “really admires socialism,” comments that Bishop converted into a campaign ad for the final legs of the race.

Bishop, in turn, is running on a familiar platform of promising to do anything Trump asks him to do, and his rhetoric echoes the president’s Nixonian paranoia. In a recent interview with Politico, Bishop “described an ‘unrelenting trifecta of opposition’ to Trump as president from Democrats, the news media ‘and even official law enforcement and intelligence agencies.’ ” His first priority as a member of Congress, he told Politico, would be “defending the president—and being vocal about that.”

Bishop is hoping that he can pull off the victory by outperforming Harris in Mecklenburg County, since it overlaps with his state Senate district, where he narrowly won reelection in 2018, and receiving a last-minute boost from Trump’s Monday rally.

That may well prove to be the case. But the last-minute, grind-it-out wins in safe Republican districts were also a common occurrence in special elections in the last cycle. In Ohio’s 12th, Georgia’s 6th, Kansas’ 4th, and Arizona’s 8th districts, Democrats didn’t win, but they came far closer than they should have—and in one case, Pennsylvania’s 18th District, the Democratic candidate, now-Rep. Conor Lamb, did pull it off. Those Democratic overperformances were a sign of what was to come. If the margin is close on Tuesday night, Republicans will have to consider the likelihood that the suburban revolt that engulfed them in 2018 could return in full force in 2020.