Democrat Conor Lamb and Republican Rick Saccone are coming down to the wire in a special congressional election in Trump Country.

Special elections are, well, special. They don’t necessarily follow recent precedents, for the simple reason that a lot of voters don’t interrupt their lives to participate in a one-off balloting. But they also, particularly at the congressional level, attract a lot of national money and attention.

Sometimes special elections have a real impact on the partisan balance between the parties, as in Alabama last December, when Democrat Doug Jones’s conquest of what everyone considered a locked-down Republican Senate seat suddenly opened an unlikely path to possible Democratic control of the upper chamber. But sometimes they are mostly symbolic in importance, which is definitely the case with the special U.S. House election in the 18th district of Pennsylvania next week. This is, in fact, a contest for a district that will not (thanks to an anti-gerrymandering decision by the Pennsylvania Supreme Court) even exist in November.

PA-18 matters for two simple reasons. First, it could confirm (or less likely, deny) the pro-Democratic trend in special elections at every level since Trump became president – a trend that should produce big Democratic gains in the midterms, and depending on their size, could flip control of the House. And second, this is an election in classic, stereotypical Trump Country, and in a district that was both solidly Republicans for years and solidly pro-Trump in 2016.

In normal circumstances, this contest should be a slam dunk for Republican candidate Rick Saccone, who faces Democrat Conor Lamb. Longtime GOP congressman Tim Murphy – whose resignation over a sex/abortion scandal forced this special election – routinely won the district easily. He didn’t even draw a Democratic opponent in 2014 and 2016. The Cook Political Report gives the district a partisan voting index rating of R+11, which means it’s 11 points more Republican than the country as a whole. And this isn’t one of those Republican districts where the president’s not very popular, like the cockpit of the biggest House special election of 2017, GA-06, which Trump only carried by a point. Trump carried PA-18 by 19 points, a margin a bit higher than Mitt Romney’s in 2012.

Additionally, Saccone is getting a lot of help from the national party and its conservative allies. The president made his second trip to the district the weekend before the balloting; the vice-president and multiple cabinet members have shown up, as has Ivanka Trump. The president’s decision to announce a plan to place tariffs on steel and aluminum imports well before the April deadline for action may have been influenced by PA-18, where protectionist sentiment has long been strong.

But the more tangible help has come from national party and outside groups, which have offset Saccone’s poor personal fund-raising with an estimated $9 million in spending. (Lamb has raised over $3 million, but isn’t getting much financial help; he’s sworn off Super-PAC money.

The anti-Lamb ads Republicans have been running are, er, interesting. Earlier in the campaign Lamb announced he would not, if he won, vote to continue Nancy Pelosi as House party leader the next time she’s up. He’s kept to a carefully centrist message, largely refusing to criticize Trump – while endorsing his tariffs – and stressing his background in law enforcement, his military service, and even his Catholicism. But here’s one prominent GOP ad:

It’s unclear how Lamb’s service as a drug gang-busting assistant U.S. attorney in the Obama administration makes him accountable for its immigration policies, much less its negotiations with Iran. But it’s part of the template for Republicans’ attacks on Democrats, so they are following it.

Lamb’s card in the hole is his close relationship with the labor movement in the district, much of which used to routinely support Tim Murphy.

He’s worked very hard to secure union support, and labor is supplying much of his get-out-the-vote muscle. And his messaging may not mention Trump, but he does go after congressional Republicans for threatening middle-class, labor priorities like Social Security and Medicare:

One of the reasons for Lamb’s strong labor support is Saccone’s record, which is not remotely as friendly to labor as was Murphy’s. The Republicans like to say that he was “Trump before Trump was Trump,” but he’s got a movement conservative strain of thinking that’s not that good politically in this part of Pennsylvania:

[U]nion leaders say Saccone’s record in the state House will hurt him with their members. He was endorsed by Pennsylvania’s Right-to-Work Committee in 2014 and he voted against a bill that expanded access to unemployment compensation.

“They don’t forget that,” [union political organizer Giles] Grinko said of union workers, noting painters rely on unemployment when work is scarce in the winter. “It’s not a Trump issue. It’s who’s doing best for their paycheck and who hurt them the most.”

Republicans hope their ultimate counterweight to Lamb’s union heft was supplied on the Saturday before the election, when the 45th president held a pop-up rally in the district. As usual, Trump went off script and made all sorts of potentially unfortunate news on subjects far from PA-18 (e.g., maligning the intelligence of U.S. Rep. Maxine Waters and casting further doubt on his willingness to meet with Kim Jung-Un), but he did get get to the point:

Trump did everything he could to tie himself to Saccone on Saturday night. He invited him on stage at the end of the rally, calling him a “good person” and a “very hard worker.” Trump didn’t downplay the significance of the race, saying the whole world was watching, but added that he didn’t want to put pressure on the candidate.

“This is a very extraordinary guy. We need him,” Trump said. “We need Republicans. We need the votes. Otherwise they’re going to take away your taxes, your tax cuts, they’re going to take away your Second Amendment rights.”

He also referred to Saccone’s opponent as “Lamb the Sham.”

It’s hard to know what’s going to happen Tuesday.

Polling in special elections is notoriously unreliable, for the obvious reason that it’s hard to figure out who will go to the trouble to vote, and you generally cannot base “likely voter” samples on past elections. In Alabama’s December special election, polls were all over the place. And polling in PA-18 has been relatively sparse, though it has shown a steady trend in Lamb’s favor. Gravis has polled the race three times, and has found Saccone’s initial lead dropping from 12 points to 6 points and then 3 points. Two very recent polls have actually shown Lamb ahead: Emerson College (48/45) and RABBA Research (48/44).

In the final days of the campaign, there has unmistakably been an effort by Republican operatives in Washington to pre-spin a possible Lamb victory as both very likely, and as entirely attributable to the fecklessness of Rick Saccone. Check out this report from Politico about a blunt message sent by National Republican Congressional Committee chairman, Representative Steve Stivers:

You need to start pulling your weight, Stivers implored Saccone, the mustachioed 60-year-old state legislator who is carrying the weight of the Republican Party in a crucial contest next week.

Stivers’ warning, described by two people familiar with the discussion, was intended to put the candidate on notice. The national GOP would be helping him out substantially, Stivers said. But if Saccone didn’t start upping his fund-raising game and getting his sluggish campaign in order, he could lose a race that should be a gimme for the party.

Stivers was right that the race should have been a GOP gimme. But that’s part of why it’s “special.” Saccone is probably still the favorite, but it never hurts to turn a underwhelming win into a giant upset (“Republican wins heavily Republican district!” isn’t an ideal election night headline for the GOP), while also preparing for possible disaster. Unless there’s a Saccone landslide on March 13 (which nobody’s talking about), any outcome is likely to be good news for Democrats looking forward. In fact, if Conor Lamb loses, he may just keep on running for the regular 2018 nomination in PA-18, which is about to become a significantly more favorable district for Democrats. And if Lamb wins, the finger-pointing and excuse-making among Republicans for an inexcusable loss in MAGA-land will intensify.