BRANCHBURG -- A big, boisterous, and combative crowd confronted U.S. Rep. Leonard Lance on Wednesday, angrily demanding that Obamacare be saved and President Donald Trump be investigated.

Lance (R-7th Dist.) was heckled when he talked about the need to make changes to the health care law, booed when he supported taking federal funding away from Planned Parenthood, and drowned out by catcalls when he refused to back U.S. Rep. Bill Pascrell Jr.'s effort to force Trump to release his income tax returns.

"There was vigor tonight," Lance said after facing the largest crowd of his 41 town hall meetings, held at Raritan Valley Community College here.

U.S. House and Senate Republicans holding town halls this week when Congress is out of session have been met with huge, angry crowds challenging their agenda, and Lance's event was no exception.

Security was ubiquitous. The 900-seat theater at the college was filled and another 400 people sat in a nearby overflow room. It was the biggest crowd Lance has drawn. Besides those inside, hundreds of demonstrators equipped with signs and slogans gathered outside long before the town hall began.

In addition to cheers and boos, audience members held up "like" and "dislike" symbols like those on Facebook.

Republican efforts to repeal the Affordable Care Act have been the catalyst for angry hordes of constituents descending on town hall meetings.

But the crowd in Branchburg, in one of just 23 congressional districts nationally that supported both a House Republican and Democratic presidential nominee Hillary Clinton, reserved its loudest cheers and its standing ovations for speakers demanding that Lance challenge Trump.

"How will you mobilize the other Republicans to push back against this man when he makes delusional statements?" asked Annette Cordasco, a Realtor from Bridgewater.

The crowd stood and cheered. "I think I struck a chord," she said.

Lance said he "always tries to lead by example" by trying "to be factually accurate."

"The issue is the Republicans need to push back when he is not honest," Cordasco persisted, as the crowd erupted in chants of "Push back. Push back."

"I certainly try to speak the truth and when the president has not spoken the truth, I indicate my disagreement," Lance said.

Sustained applause also greeted Jim Girvan of Branchburg, who is retired, when he asked Lance to support efforts by Pascrell Jr. (D-9th Dist.) to have the House Ways and Means Committee use its powers under a 1924 law and request Trump's tax returns.

"I think the Ways and Means Committee shouldn't be investigating the returns of a private individual," Lance said.

"He's the president," Girvan shot back.

The ACA was the first question. Lance, a member of the House Energy and Commerce Committee that has jurisdiction over health issues, twice this year backed measures making it easier to repeal the measure.

That led Caroline Scutt, a councilwoman from Frenchtown, to ask to loud applause, "Why repeal? Why not reform?"

Lance said he leaned toward repair. "I do not favor repeal without there being a replacement in place."

Outside, protestors demanded Lance support the health care law.

"I think the solution is for people like Congressman Lance, who I'm sure has strong moral principles, to stand up and vote his conscience and principles and not follow the party line," said Marsha Goldstein of Flemington, carrying a sign reading, "Now you've pissed off Grandma."

The line of demonstrators was so long that different sections engaged in different chants, unable to hear the others as they shouted, "We will remember next November," "Vote him out," and "All day, all night; health care is a human right."

"I don't want to just sit around," said Kassy Llanos, 14, a freshman at Warren Hills Regional High School. "I want to stand up and make an impact on change."

One of those speaking through a megaphone was Peter Jacob, a Democrat endorsed last year by U.S. Sen. Bernie Sanders (I-Vt.) as he ran against Lance, garnering 43 percent of the vote. He said he was "pretty positive" he would try again in 2018.

"I wish all these people came out just a year ago," Jacob said afterwards. "They're seeing the gravity of the situation now.

The town hall attracted national attention as supporters of the health care law have confronted Republican lawmakers over plans to repeal it, a mirror image of the Tea Party protests of eight years ago in which Democratic members of Congress were harangued by opponents of the proposal to expand health coverage.

Those protests helped fuel a wave of support for Republicans that helped them win back control of the House. Democrats hope to catch a similar wave in 2018.

"In 2009, advocacy on the Affordable Care Act was purely ideological," said Emily Tisch Sussman, campaign director for the Center for American Progress Action Fund, the advocacy arm of the research group founded by John Podesta, Clinton's campaign chairman. "Now, it's actually practical. People are relying on it for life-saving care."

A Quinnipiac University poll released earlier this month said 50 percent of U.S. voters opposed repeal. while 46 percent supported it.

"If the town hall fervor is just a group of Democrats who voted for Hillary Clinton and are just being more vocal in public, I'm not sure it changes the electoral equation," said Nathan Gonzales, editor and publisher of Inside Elections, a Washington-based publication that tracks congressional races. "If these are people who didn't vote in the 2016 elections, if there are people who voted for Donald Trump, that has the potential to change the math."

The health care law has provided coverage under Medicaid to 194,000 New Jersey residents, tax subsidies to help buy insurance to 205,242 people in the state, and extra help to buy prescription drugs to 211,881 seniors, according to the U.S. Department of Health and Human Services.

What will GOP actions mean back home in NJ? Rep. Lance takes questions during a crowded, much-anticipated town hall event following GOP discussions around repealing the Affordable Care Act. Posted by NJ.com on Wednesday, February 22, 2017

Jonathan D. Salant may be reached at jsalant@njadvancemedia.com. Follow him on Twitter @JDSalant. Find NJ.com Politics on Facebook

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