His seat at risk, U.S. Rep. Tom MacArthur tries to thread the Trump needle in tense race vs. Democrat Andy Kim in N.J.

U.S. Rep. Tom MacArthur is on the phone with the 50-and-over crowd, 1,200 of them in fact.

He's downplaying the legislative act that has defined him, the one that landed him triumphantly in the Rose Garden, flanked by President Trump and other Republicans; a YouTube moment from May 2017, as they celebrated House passage of a bill that would have repealed the Affordable Care Act.

"I have a feeling, come election time, you're going to end up regretting this visual," wrote the first commenter on YouTube.

Election time has arrived, and MacArthur, the only congressman from New Jersey to vote with Trump on both health-care repeal and the tax-cut bill, is in a fight against Democrat Andy Kim to save the seat in Congress that made his name synonymous with attempts to repeal Obamacare.

That health-care amendment that bears his name, credited with saving, temporarily, the Republican effort to repeal the law?

"It was only a two-page amendment," MacArthur tells the seniors on this nearly one-hour-long AARP telephone town hall. "A lot has been made of this so-called MacArthur amendment."

A lot has. On television screens, in mailers and debates, the amendment, which would have allowed states to seek waivers from a ban on charging people with preexisting conditions higher premiums, has been characterized — by the AARP, host of the call — as an "age tax."

In a district with 140,000 seniors, MacArthur acknowledged that a lot of people ask him about the "age tax," which he has dismissed as a "figure of speech" and not a real tax, "fear mongering" derived from an AARP analysis of possible rate increases that would affect a small segment: people ages 50 to 64 insured under the Affordable Care Act.

For MacArthur, who has long touted his arguably overlooked bipartisan credentials alongside his arguably proud ties to Trump, the campaign's closing days have him trying to thread the needle, spinning a more complex tableau for his polarized Ocean County and Burlington County Third Congressional District, assuring voters he represents them "whether you like Trump or not."

After a barrage of Trump-like negativity and eyebrow-raising ads attacking Kim, MacArthur is going "positive" — a sign that the moderate and independent voters of suburban New Jersey might need some tending if MacArthur, a Connecticut native and former insurance executive who was a North Jersey mayor and now owns houses in Toms River and on Long Beach Island, is going to keep his Washington job.

It's a case he's tried to make all along, since before he split with the entire New Jersey congressional delegation by voting for the tax bill that capped the deduction on state and local taxes (SALT) at $10,000. MacArthur says that without his intervention, the allowable amount would have been zero.

In recent weeks, he's made sure to highlight the nuances of his positions. He held a news conference about Trump's tariffs — to show he managed to get one lifted for PMC Group, a Mount Laurel company that depended on a chemical only available in China.

He says he tried to convince House Speaker Paul Ryan — whose Congressional Leadership Fund has financed some of the most negative ads against Kim, including a widely denounced commercial calling the Marlton-born son of South Korean immigrants "not one of us" — that Republicans should work with Democrats on issues like immigration.

This week, MacArthur was quick to distance himself after Trump said he would try to end birthright citizenship.

"Tom has long supported birthright citizenship," spokesperson Chris Russell said.

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That followed a week in which MacArthur's chief of staff, Frank Luna, identified three legislative priorities stressing either bipartisanship or a willingness to oppose Trump: the tariffs, in which the congressman intervened on behalf of PMC; an opioid law that grew out of a bipartisan task force he co-chairs; and school safety bills, including a bipartisan Mental Health and Public Safety Partnership Act.

"We need people that will work with the president when he's right, and that will stop him when he goes down the wrong path, which he does sometimes," MacArthur said in an interview this summer. (MacArthur did not make himself available for this story despite repeated requests.) "That's who I am. And guess what? He listens to me more than he listens to somebody who's shooting spitballs at him all the time."

Matthew Hale, political science professor at Seton Hall University, said MacArthur's latest ad is revealing.

"The fact that he now seems to be saying, 'Oh, and by the way I'm bipartisan,' means that this is a really close race," Hale said. "He feels like he's tapped out all of the core Trump supporters and hard-core Republicans, and it's not enough."

Never mind that MacArthur and his allies have been pounding Kim, a Rhodes scholar who served as a national security officer under President Barack Obama, with negative ads for months: tax cheat, liar, carpetbagger, "Real Fishy," Nancy Pelosi liberal. He's also mocked Kim's own bipartisanship claim: a five-month entry-level stint under President George W. Bush.

The Tom MacArthur of late October is all harmony and nuance.

"All this division and hatred is not good for America," he told the seniors on the line with AARP. "You won't find me taking cheap shots or being ugly with people who disagree with me."

Republican voters like Kathy McLean of Ocean County, which gave Trump the highest margin, 94,000 votes, of any county in New Jersey, say they never viewed MacArthur as a clone of the president.

"He's not a straight Republican," McLean said. "I don't think anybody from Jersey is."

MacArthur says his health-care plan would have preserved coverage for pre-existing conditions, though analysts said it would have allowed insurance companies to price people out of the market.

And the tax plan, he says, doubled the standard deduction for people who don't itemize.

Anyway, as MacArthur supporter Mike Phillips, 68, of Stafford, asked, "Why isn't the burden put on New York and New Jersey to lower taxes? It's not Trump's fault or MacArthur's fault."

Outside the Stafford Diner, Phillips echoes a lot of voters in the heavy media market of the Third District in saying he's tired of the negative ads, but he seems to have been influenced by them, citing anti-Kim talking points like "carpetbagger" and mentioning the hot-button topic of U.S. Rep. Maxine Waters, another Democrat who is a frequent target of Trump.

But the Republican loyalist might still give MacArthur pause about touting Trump, who, Phillips said, "should tone it down." He said he felt "lukewarm" about MacArthur, but added, "In this environment I couldn't vote for a Democrat."