The NRA spent $7,868 in support of Saccone but the money wasn’t seen in a high-profile venture like TV ads or get-out-the-vote efforts. Most of it - $7,532 - was spent on mailings scheduled to be distributed in the district on Monday. The remaining $336 was spent on phone banking earlier this month, according to campaign finance filings.
The group confirmed the existence of the mailer to ABC News but declined to describe it or where it was sent in the 18th Congressional District. The NRA has endorsed Saccone, who has an A+ rating from the group, and has donated $2,450 to his campaign.
And it isn't the only spending entity making this an issue in the race.
The campaign tactics also come as Republicans go all-in for this special election contest in a district Trump won by 20 points in 2016 and won’t exist in the November election because of redistricting.
Democrat Conor Lamb has run a strong race, putting a seat in play for the party where it should not be competitive. And the national GOP has already started the post-election night spin, talking down Saccone as a bad candidate who couldn’t fund-raise or campaign properly.
For both sides the stakes are high. If Lamb wins, Democrats will claim their candidates can run and win anywhere in the country – even ruby-red Trump districts - which will boost their odds in retaking control of the House this fall. If Saccone wins, Republicans will argue they can keep the House even with the president’s low approval ratings and the consistent flow of chaos and controversies that come out of the Trump White House.
Money has poured into the contest.
Lamb raised more than $3.6 million since January, compared to Saccone's haul of just under $1 million over the same time period, according to FEC data.
Pro-Lamb outside groups have spent about $1.7 million.
Gun rights are a big issue in this red district, which contains parts of rural south-western Pennsylvania, where hunting is a huge tradition.
And, in the aftermath of the Parkland shooting, Lamb called for tougher background checks but not stricter gun laws.
Additionally, at a rally on Sunday, United Mine Workers President Cecil Roberts called Lamb a "God-fearing, union-supporting, gun-owning Democrat.”
The CLF mailer, ironically, highlights that record. The flyer, obtained by ABC News, reads: “THANK YOU CONOR LAMB FOR OPPOSING GUN RESTRICTIONS.”
But the recipients were Democrats in Allegheny County, likely in hopes of suppressing turnout among the more liberal Democrats who live in the Pittsburgh suburbs that make up that part of the district; a group of voters that supports more restrictions on guns.
“Our job is to make sure voters in Pennsylvania’s 18th District know where Conor Lamb stands on important issues of the day. This mailer was sent to voters who might find his views on the Second Amendment of note,” said CLF spokeswoman Courtney Alexander in a statement.
Lara Putnam, a professor at the University of Pittsburgh, said that part of the 18th Congressional District is more liberal and more likely to favor gun control.
“If it’s going to the northern part of the district is probably says Conor Lamb supports guns and it’s trying to get the sort of suburban progressive Democrats in the northern part of the district to stay home,” Putnam, who lives just outside the district and has canvassed for Lamb, told ABC News.
But the rest of the district is composed of more rural areas that strongly support gun rights, including parts of Washington, Greene, and Westmoreland Counties.
ABC News’ Soorin Kim contributed to this report.
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