The announcement of first-term Rep. Katie Hill’s (D-Calif.) resignation attracted national headlines primarily because of the titillating details of the sex scandal that derailed her career. But the special election to choose her successor next year will garner more important national headlines, as it could serve as the first barometer of the nation’s political mood.

Hill’s district was a Republican stronghold before President Trump. It regularly voted for (losing) Republican statewide candidates and sent Republicans to Congress and the state legislature even as the ranks of Republican officeholders decreased across California. It even contains the Ronald Reagan Presidential Library, the closest thing conservatives have to a holy shrine. But Trump changed all that.

California’s 25th Congressional District is now prime marginal real estate. Hillary Clinton beat Trump there despite the district’s past, and Hill clobbered GOP incumbent Steve Knight by more than 8 percentage points in 2018. Republicans also lost a state assembly seat they had long held that contains the 25th’s largest city, Santa Clarita. This is why most sophisticated political prognosticators are initially rating the special election as “leaning Democratic.”

That cautious ranking, however, underestimates the continuing Republican lean of the area’s residents. The GOP held another assembly seat covering the populous Antelope Valley portion of the district in 2018, even though that seat was carried by President Barack Obama in 2012. Republican gubernatorial nominee John Cox also lost the seat last year by only 2 percentage points to Democrat Gavin Newsom, even while Cox was losing the state by more than 23 points. In short, this seat remains wide open to voting for Republicans even in the depths of California’s flight from Trump.

This is almost certainly due to the district’s demographics. The 25th is a fast-growing, exurban region — the sort of place where young families settle to raise their children when they can’t afford pricey real estate closer to Los Angeles. As a result, it is more middle-income and moderately educated than many of the longtime Republican-held seats that flipped last year. These swing voters will largely be the ones who decide the 2020 election as they weigh their somewhat-conservative policy leanings against their feelings about Trump. The special election here, then, will be an early sign on how they are leaning.

The election will be a two-step affair. A primary election will be called for early next year, likely March 3, so that it coincides with California’s Democratic presidential primary. A candidate is elected if he or she receives 50 percent of the vote. If that does not occur, the top two candidates regardless of party will then advance to the general election sometime in the spring. That setup encourages both parties to settle on one strong candidate early so that neither party runs the risk of being shut out in the general.

Two potential Republicans would clearly be strong contenders. State Sen. Scott Wilk (R-Santa Clarita) already represents 73 percent of Hill’s seat and previously represented the 38th assembly district for four years before ascending to the senate in 2016. He would start as a known commodity to most of the seat’s voters and would also be able to transfer some of the nearly half-million dollars in his state campaign account to the federal race. But the man Hill defeated last fall, former representative Steve Knight, is also considering a run. He would also have districtwide name identification but would have to overcome the factors that led to his defeat.

The GOP will want someone of their stature to compete with the likely Democratic nominee, State Assemblywoman Christy Smith. Smith, who announced on Monday that she would seek the seat, flipped Wilk’s old assembly seat last November. California state legislative races are big-money affairs, and Smith raised more than $2.2 million in her successful effort (Wilk raised more than $2.6 million in his 2016 election). Smith reported about $369,000 cash on hand in her state account as of June 30, giving her a leg up on potential contenders.

The GOP has other potential contenders should Wilk or Knight demur. State Assemblyman Tom Lackey (R-Palmdale) has represented about half of the 25th since 2014. He has fought three straight tough races and had $175,000 cash on hand at midyear. Former naval officer Mike Garcia, who was already running against Hill, reported raising a total of $525,000 as of the first week of October. Either of these people could conceivably raise the resources needed to make this a competitive race.

Republicans have no chance of retaking the House if they cannot retake seats like the one Hill is vacating. How fitting it would be if they could win one for the Gipper and make his final resting place the first seat they retake on the way back to power.

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