President Trump, right, talks with Republican Rick Saccone during a campaign rally on Saturday in Moon Township, Pa. (Keith Srakocic/AP)
Opinion writer

In the final poll before the attention-grabbing special election to fill Republican Tim Murphy’s seat in Pennsylvania’s 18th Congressional District, the Monmouth University poll showed Democrat Conor Lamb up by 6 points over Republican Rick Saccone, a lackluster candidate for whom Republicans pulled out all the stops. President Trump came out for a barn-burning rally on Saturday; Republicans have invested more than $10 million, a gigantic sum for a special election outside a major media market. If Trump’s tariff announcement was intended to help Saccone, it seems to have failed. “Fully 96% of likely voters, though, report that the tariff announcement did nothing to change their vote in this race,” the pollsters found. “A bare plurality of likely PA18 voters say that the tariffs will help (43%) the local area’s economy, but a sizable number (36%) feel these tariffs will actually hurt the region. Another 8% say the tariffs will have no impact and 13% are not sure what the impact will be.”

Trump’s performance has left residents underwhelmed. (“The poll finds that likely voters in PA18 are divided on the president’s overall job performance – 49% approve and 49% disapprove. Last month, Trump earned a slightly positive 51% approve and 47% disapprove rating.”)

On Monday, Saccone seemed to lose it. President Trump’s opponents, he asserted, “have a hatred for our country. … They have a hatred for God.” This was not the voice of a confident candidate.

Deep in Trump country, this should have been a slam-dunk for Republicans. FiveThirtyEight reminds us that before Murphy, “the Republican had won eight consecutive elections in this district by margins of no fewer than 15 percentage points. In both 2014 and 2016, no Democrat even bothered to run against Murphy. President Trump carried the 18th District by nearly 20 points (58 percent to 39 percent); Mitt Romney won it by a similar margin in 2012.” In other words, this race should not be close.

Republicans — in what surely amounts to a vote of no confidence in Saccone — are already blaming him as a lackluster candidate. By contrast, Democrats seem to have hit the jackpot with a telegenic, conservative Democrat who served in the Marines and as a U.S. attorney. (“He’s not a vocal advocate of greater gun control and publicly seems ambivalent on the matter of abortion: a Catholic, he’s spoken out against certain pieces of pro-life legislation while also echoing his personal unease with the practice,” Time magazine reports. “His bread-and-butter issues are supporting labor and combating the opioid crisis. He’s already earned the support of a number of unions in the region.”)

If Saccone pulls it out, Trump will take full credit, but Republicans should forgo celebration and try to figure out why this was remotely competitive. Trump and Saccone dropped their tax message, which seemed to generate shrugs in this blue-collar district. Is the tax plan a help or a hindrance? Trump trotted out all the hot-button themes (e.g. insulting female lawmakers, mocking the press, threatening to execute drug dealers), but those issues may have lost their punch. And frankly, Trump’s stump speech sounded stale. In short, Republicans may lack a compelling theme if voters are not particularly inclined to vote Republican in order to boost Trump.

If Lamb does win, Republicans will be in justifiable panic. (The difference between a narrow loss for Republicans and narrow win will be psychologically huge, even though both should portend real trouble for the GOP in November.) The problem will remain, however: What to do about it? Republicans from deep-red states will still be petrified to break with Trump; Republicans in swing districts can only run so far from the president (especially if they voted for his tax plan and for his Obamacare repeal efforts). Fears of a blue wave may become a self-fulfilling prophecy as donors decide not to throw good money after bad. Voters become more discouraged, thereby depressing turnout. And conversely, Democrats will receive another shot of adrenaline.

The realization that the Pennsylvania 18th won’t survive court-ordered redistricting has not diminished both sides’ interest in the race. Each side hopes this is an indication of things to come. However, the signal is unmistakable: If Republicans have to struggle to win a seat like this, they’re in for a shellacking in the scores of more Democratic-friendly districts. Come to think of it, they might get a jump on the results and start panicking now.

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