In an interview with Fox News' Sean Hannity, Pence says "the only thing at stake is everything" in the race between Republican Rick Saccone and Democrat Conor Lamb. Lesson among faction one: elected Republicans should stick to traditional party priorities and give Trump and Trumpism a wide berth. Lamb, a Marine veteran and former federal prosecutor, has outraised Saccone by more than 3-to-1, blanketed television and crisscrossed the district more aggressively than the GOP nominee.
Some Republican operatives, speaking on condition of anonymity, have been laying part of the blame on Saccone's skills as a campaigner.
During a recent campaign speech, Moulton said Lamb should go to Washington because he's willing to take on members of his own party who "just aren't getting it done". Trump campaigned for Saccone in Pennsylvania on Saturday night. They've painted Lamb as a lackey of House Democratic leader Nancy Pelosi of California and weak on immigration.
Pennsylvania politicos, meanwhile, are baffled by the Republicans' decision to put Saccone on the ballot. The National Republican Congressional Committee almost matched that sum. "I don't know much about Rick Saccone", he acknowledged, adding that he remains skeptical about Trump. A Republican loss here would be the second such result in which Mr Trump has intervened in the past three months, an ominous omen ahead of November's all-important midterm elections.
Trump's footprints are all over southwest Pennsylvania.
The Congressional Leadership Fund, a political action committee aligned with House Speaker Paul Ryan, at one point deviated from its Pelosi-bashing scripts to send Democratic voters mailers praising Lamb for opposing new gun restrictions.
Trump Jr. began his Monday tour of the campaign trail in front of a giant candy castle, of which every part was edible except the carousel.
But there's no sign the Republican president's move has reversed Lamb's momentum.
But for now, in a deeply gerrymandered district whose far-flung constituents have little in common ideologically, educationally, economically or culturally, the election will be decided not by any policy nuance or local infrastructure plan but by a brutal calculus: Which 18th District will turn out the most voters on March 13? That number includes about 17,000 steelworkers.
The bulk of the president's remarks focused more on a reboot of the "Make America Great Again" campaign in a review of what he has done - and will do - in office, such as touting the tax cuts he signed past year, and talking about his decision to accept talks with North Korea over the country's nuclear program.
Saccone has been a union foe at the statehouse - a break from the union-friendly Murphy, whose labor backing was a key reason Democrats couldn't topple him.
Any kind of Democratic triumph would be portrayed in the media as Mr. Lamb riding the great "blue wave" the Democrats have been trying to locate on the horizon since they were drowned in a similar red wave 18 months ago. The tariffs on steel and aluminum Trump has announced are tailor-made for blue-collar neighborhoods outside Pittsburgh, though the once-fabled "Steel City" has diversified its economy around sectors such as technology and health care in the 21st century.
Republicans privately agree, even as they look to pin the blame mostly on Saccone and downplay what it would mean to lose a deep red, culturally conservative district after a brutal loss in an Alabama Senate race late past year, a beat-down in Virginia's gubernatorial race, dozens of losses of state legislative seats and a number of close calls in House special elections.
The race will be the first major test of how the new tax law is playing with voters. He squares off Tuesday against Democrat Conor Lamb in the special election for Pennsylvania's 18th District.
Groups supporting GOP candidates have spent more than $10 million on the race, according to published reports.
The Democrat's efforts also have been effective enough to frustrate and even spook Republicans.
Von Wertmann, who says he often fluctuates "about 50-50" between voting for Republicans and Democrats in election cycles, said he supports Lamb for not operating "on the fringes" of liberalism. And the party had managed to hold on in House races, including one in the Atlanta suburbs last spring.
But Lamb has offered a potential antidote.
Lamb, 33, has been hard for Republicans to depict as a liberal because of his background, message discipline and mixed political views that include opposing Pelosi (D-Calif.) and supporting more natural-gas drilling.