WASHINGTON -- Republican Rep. Scott Perry, a past chairman of the hard-right House Freedom Caucus, has spent his 12-year career in Congress railing about the ballooning national debt and deficits -- what he's bemoaned as the "bankrupting of America."

But after voting for President Donald Trump's "big beautiful bill," which is estimated to hike deficits by more than $4 trillion over the next decade, Perry finds himself playing defense on the issue of the skyrocketing national debt.

"He pretends he's a fiscal conservative, but this is $4 trillion of new debt," said his likely Democratic challenger, Janelle Stelson, a former local news anchor who is seeking a rematch against Perry in 2026. "I mean, the next generation is really going to struggle with this. We're mortgaging our children's future with that $4 trillion."

Perry's a "fraud," Stelson added. "This is a really rotten vote that's really going to hurt people."

Stelson is just one of a handful of Democratic candidates turning the tables on vulnerable Republicans this cycle on the issue of rising deficits -- a campaign issue that helped propel House Republicans to power in the 2010 Tea Party wave and which the GOP has consistently returned to in more recent elections.

In Wisconsin, Democratic challenger Rebecca Cooke is attacking GOP Rep. Derrick Van Orden for "plunging our country into debt to appease Trump and billionaires." In Iowa, Democrat Christina Bohannan said Republican Rep. Mary Miller-Meeks "voted to blow up the national debt by 3.4 trillion dollars" and that "Iowa can't afford another term of MMM in DC."

And in New Jersey, Democrat Rebecca Bennett is going after GOP Rep. Tom Kean Jr., saying he "chose to make life harder for families by raising costs, exploding the national debt and ripping healthcare away from 20,000 people across our district."

Republicans argue that the $4 trillion estimate by the nonpartisan Congressional Budget Office is grossly overstated and fails to take into account that revenue generated from the bill's policies would boost economic growth and help fill government coffers.

"If you explain it the right way, [Trump's law] actually is intended to reduce the deficit over time," Rep. Young Kim, who has frequently spoken out about the national debt, told NBC News. "We can't do it overnight, but the fact [is] that we're doing it incrementally."

Kim, a vulnerable Republican representing California's Orange County, has faced criticism from one in a large field of Democrats hoping to unseat her, with Democrat Esther Kim Varet, a Los Angeles art dealer, labeling her a "hypocrite" for voting to "balloon the national debt to $40,000,000,000,000.00."

But Kim said Democrats and the media covering the CBO score have it wrong. "Contrary to what you guys are reporting, it is actually helping to reduce the deficit over time," Kim said. "So people understand that."

And House Republicans' campaign officials said their incumbents won't be lectured by a Democratic Party that saw the national debt climb by trillions of dollars during the Biden administration. During his Senate confirmation hearing, Russell Vought, Trump's pick for budget director, testified that the federal debt climbed $8.4 trillion under Joe Biden, but also $7.8 trillion during Trump's first term.

"Democrats spent years maxing out the nation's credit card on Biden's reckless spending spree, and now they want to lecture Republicans on fiscal responsibility?" asked Mike Marinella, a spokesman for the House GOP's campaign operation, the National Republican Congressional Committee. "Republicans are delivering tax relief, economic growth, and real deficit reduction, while Democrats can't erase their long record of blanket support for endless spending to push their crazy, radical wish list and endless opposition to middle-class tax cuts."

In two brief interviews at the Capitol, Perry conceded that he wasn't happy that the Trump law would add to the deficit. "Obviously, I don't like that," he said. "Of course, Washington, D.C., is often about compromise, and the things that you don't love about a piece of legislation you have to accept for the things that you do want."

But he argued that he and others in the Freedom Caucus helped secure changes to the Trump legislation that brought its cost down by more than $1 trillion -- imposing work requirements for Medicaid recipients, restricting food assistance for certain legal residents and rolling back clean energy tax credits from Joe Biden's Inflation Reduction Act.

The new law extended the 2017 Trump tax cuts, which were set to expire at the end of this year, and that outweighs any of the bill's negative impacts, Perry said.

"Putting thousands and thousands of dollars in taxes on our citizens was not going to help them, the economy," Perry told NBC News. "And remember, I'm one of the guys that fought to take it from $300 billion [in cuts over 10 years] to $1.6 trillion. It's not enough, but that's a pretty good effort.

"People didn't send me to Washington to raise their taxes, but they also didn't send me to bankrupt their country," he added.

Told that Stelson has been referring to him as a fiscal "fraud," Perry suggested that she's an empty suit who is recycling talking points from Democratic campaign operatives.

"You should ask her to explain anything that she just said, because she's being fed responses or quotes from the party that's running her campaign," Perry said, "and she has no idea what she's talking about."

The race in Pennsylvania's 10th District, based in the state capital of Harrisburg, will be one of the most closely watched this cycle as Democrats try to win back control of the lower chamber -- and secure a check on Trump.

In 2024, Perry edged out Stelson, 50.6% to 49.4%, or by just 5,133 votes out of more than 400,000 cast.

An Iraq War veteran and former state lawmaker, Perry arrived in Washington in 2013. Like many in his party at the time, he warned about rising deficits and debt in the wake of Democrats' passage of the Affordable Care Act. He later served for one term as chairman of the Freedom Caucus, created to pull the GOP conference further to the right, especially on spending matters.

"It's complete hypocrisy," said fellow Pennsylvania Rep. Brendan Boyle, the top Democrat on the Budget Committee. "Besides this bill being the greatest loss of health care in American history, it's also the single greatest increase to our national debt in American history. Every single Republican, with the exception of two, voted completely contrary to their principles and voted for what is really a debt bomb."

Other endangered swing-district Republicans are facing similar attacks. In Arizona, Democrat Marlene Galán-Woods, who is running in the primary to take on vulnerable GOP Rep. David Schweikert in the wealthy Phoenix suburbs, has referred to him as a "hypocrite in chief" over his support for the Trump bill.

"His hypocrisy is deafening as this 'fiscal conservative' 'deficit hawk' supports a bill that adds trillions to the debt. He's got to go," Galán-Woods, a former broadcast journalist, posted on X.

Schweikert rode the 2010 Tea Party wave to Washington and was one of the founding members of the Freedom Caucus, but left the group in 2023. The wonky chairman of the bicameral Joint Economic Committee, Schweikert has given countless floor speeches and interviews on the risk of deficits and the national debt, accompanied by floor charts and graphs.

In an interview, Schweikert said the CBO score showing the Trump law will add trillions to the deficit "absolutely gives me heartburn."

He said as Republicans debated the legislation, he offered several amendments to pay for its price tag, including one to reform the Medicare Advantage program by tackling waste and fraud.

"Guess how many sponsors I have? ... Zero," Schweikert said. "Not a single member of Congress will sponsor my bills. Why? It has the word Medicare in it, and you'll beat the living s--- out of them if they sponsor something that has the word Medicare."

In the end, he said, he voted for the bill to spare his constituents from a horrible tax increase.

"But there becomes my intense frustration: I'm not gonna let the taxes go up on my constituents. You didn't have a choice. In parts of my district, it would have been 3,000 bucks a year" in tax hikes, Schweikert said.

Officials with the National Republican Congressional Committee countered that Galán-Woods has praised Biden's Inflation Reduction Act (IRA). The CBO initially estimated that the law would cut the deficit by $58 billion, but CBO Director Phillip Swagel told reporters this year that the IRA's clean energy tax subsidies would increase deficits by $825 billion over 10 years. A separate Goldman Sachs estimate showed those subsidies would cost $1.2 trillion over 10 years.

The GOP officials also noted that Galán-Woods and Stelson strongly opposed extending the 2017 Trump tax cuts.

Boyle, the ranking Democrat on the Budget Committee, defended the CBO from GOP attacks. He noted that Congress has oversight of that budget office, which has been led by Swagel, an assistant treasury secretary during the George W. Bush administration, since 2019.

"The CBO is headed by a Republican appointee and staffed by 270 hardworking, nonpartisan government officials who simply call the balls and strikes as they see them," Boyle said.

"It's not just CBO that's showing the so-called big beautiful bill will add a massive amount to the national debt -- it is left-of-center groups, it is right-of-center groups and it is nonpartisan groups," he said. "Their piece of legislation pretty much united every group across the ideological spectrum that this is really a debt bomb."

Republicans who came to Congress to fight the deficit face attacks for raising it under Trump