Standing in front of a few dozen supporters in a strip-mall parking lot in Ocala, Florida, on Monday evening, Democratic congressional candidate Josh Weil made a prediction.

The public school maths teacher said that in less than 24 hours, he was going to make history by flipping a solidly Republican congressional seat ? helping to wrest control of the House of Representatives from the Republicans.

"Their 2025 agenda stops here," he promised, railing against President Donald Trump and Elon Musk's efforts to slash government services and personnel.

Just an hour earlier, in a telephone town hall meeting, Randy Fine, his Republican opponent in Tuesday's special election, had a similar message ? although he framed it as a warning, not a promise.

"Democrats are mad," he said. "They're going to do whatever it takes to grind Donald Trump's agenda to a halt."

Voters in the eastern half of central Florida, from Ocala to the towns north of Daytona Beach, head to the polls to fill the seat vacated by Michael Waltz, chosen by Trump to be national security advisor. Waltz recently sparked a media frenzy after inadvertently adding a prominent journalist to a high-level group chat about the US strikes in Yemen.

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That Waltz's job may now be in jeopardy is just one reason Tuesday's contest for one of the 435 House seats is now a national story.

The other is that Weil, despite running in a district Trump carried by more than 30 points last November, just might win. And if he does, Democrats would take a big step closer to a majority in the narrowly divided House.

Win or lose, the race also could serve as a barometer of voters' motivation as Trump begins his second term ? and offer hints at the political landscape ahead of next year's mid-term congressional elections.

It is one of two special elections in Florida on Tuesday. The other, in Florida's panhandle region, will determine a replacement for Matt Gaetz, the firebrand congressman Trump originally picked to be attorney general before he withdrew under a cloud of sexual misconduct and ethics allegations. A Republican is widely expected to win there.

But that is not the case here. Weil has raised about $10m in campaign donations, dwarfing the $1m brought in by Fine, a Florida state senator.

According to a recent public opinion survey, Weil narrowly trails Fine. An internal poll by a respected Republican firm reportedly showed Weil ahead by 3.

That's enough to cause more than a little anxiety in Republican ranks.

"There's no excuse for a Republican not to win this race," said Randy Ross, a Florida-based conservative activist who campaigned there for Trump in 2016 and 2024. "The only excuse that can possibly be had is Republicans weren't excited and didn't get out to vote."

Mr Ross added that Republican voters need to understand that Fine will support Trump's agenda in Congress ? and Weil will not.

To this end, some of the party's heaviest hitters stepped in to help. Last Thursday, Trump joined the Republican candidate in two telephone town hall events. On Monday night, Florida Congressman Byron Donalds and conservative commentator Ben Shapiro held their own event.

"Donald Trump's agenda is hanging by a thread," Shapiro said. "This is a district that simply cannot fall into Democratic hands."

Tech multi-billionaire Musk, a close Trump ally, may be campaigning in person for a hotly contested Wisconsin Supreme Court race, but his political committee directed more than $75,000 to support Fine in recent days. Other conservative groups followed suit, helping Fine level the financial playing field.

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Of particular concern for the party is that special elections take place during times of lower political engagement and usually involve only the one race in question. They often tilt toward the party with the most enthusiasm, according to Mr Ross. For Republicans, a Democratic show of strength on Tuesday would be troubling.

"You can't go just on name recognition in a special election," he said. "You've got to drive people out to vote for you."

Republican nervousness is a result of simple math in the House of Representatives. With a 218 to 213 majority in the 435 seat chamber, the party cannot afford to lose any winnable elections ? let alone ones that should be a slam dunk.

While a Weil victory alone wouldn't be enough to flip control of the chamber, two of the currently vacant seats are in safely Democratic districts. If the results of those special elections go as expected, Democrats would be on the verge of control.

That could explain why the president announced on Friday he was withdrawing his pick of New York Congresswoman Elise Stefanik to be US ambassador to the United Nations, despite her having all but formally vacated her office. A Weil victory on Tuesday would mean the Republicans could not afford to lose a New York election to replace Stefanik.

Even before Tuesday's balloting, both Democrats and Republicans jockeyed to frame the results in the best light for their party.

Conservatives downplayed the national implications of the race and placed blame on Fine, who has been accused of running a lacklustre campaign and taking victory for granted.

"It's a reflection of the candidate that's running the race, " Republican Florida Governor Ron DeSantis said of Fine's apparent underperformance.

Meanwhile, Democrats are declaring a victory ? at least, the moral variety.

"These are races that should not, under ordinary circumstances, be on anyone's political radar," Democratic House Minority Leader Hakeem Jeffries said last Monday. "The American people are not buying what the Republicans are selling."

That sentiment was echoed by many of Weil's supporters on Monday night in Ocala, even if the candidate himself told the BBC he would win by eight points.

"If we lose but come close, moderate Republicans might take notice," said Buddy Oswald, an attorney and educator. If they were worried their party could lose a safe seat, he added, maybe they would feel the heat and be more willing to break with the president.

Eight years ago, in the aftermath of Trump's stunning 2016 presidential victory, Democrats sought solace in special election races across the map. They pulled off some stunners, including a Doug Jones Senate victory in deeply conservative Alabama. In other races, such as a bid by Jon Ossoff in a suburban Atlanta district, the Democrat came up just short.

Those races presaged a high level of Democratic enthusiasm that led to a wave in the mid-terms the following year, when the party won 39 seats in taking back the House of Representatives and putting a decisive end to Trump's first-term legislative agenda.

Republicans, with convincing victories on Tuesday, want to squelch any chance of history repeating itself.

Democrats, engaged in a sometimes acrimonious debate over strategy and political priorities, would like Florida to get them back in the win column ? or at least give them hope of better days to come. (BBC)

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