Shotgun-toting Manchin shoots anti-Obamacare lawsuit in new ad for re-election bid in West Virginia "I’ll still take on anyone that messes with West Virginia," Manchin says.

Invoking the same colorful imagery he used in his 2010 re-election bid, West Virginia Democratic Sen. Joe Manchin released a new ad Monday literally taking aim with a shotgun at the most recent lawsuit against the Affordable Care Act, which would dismantle protections for individuals with pre-existing conditions.

"I haven’t changed," Manchin asserts in the ad. "I might be a few years older and I’ll still take on anyone that messes with West Virginia. Now the threat is Patrick Morrisey’s lawsuit to take away health care from people with pre-existing conditions. He is just dead wrong and that ain’t going to happen."

The ad reflects his 2010 strategy, when Manchin first ran for the U.S. Senate and released an ad featuring him firing a rifle at an anti-coal cap-and-trade bill that was supported by members of his own party, including then-President Barack Obama.

Again promoting dual themes, this new ad showcases Manchin’s support for the health law that has repeatedly been threatened with repeal by Republicans who seemingly always fall short, as well as his continued support for the Second Amendment in an overture to gun-toting West Virginians who strongly seek to protect the right to bear arms.

The new lawsuit, which aims to strike down Obamacare, was brought before a Texas court this month by the Justice Department and 20 Republican attorneys general, led by Texas’ Ken Paxton and includes Manchin’s opponent in the general election, West Virginia Attorney General Patrick Morrisey.

The attorneys general argue that the federal health law is unconstitutional after Congress weakened it by eliminating the individual mandate through the GOP tax bill passed last year.

"West Virginia has been hurt by lying liberal Joe Manchin putting the interest of Washington liberals ahead of the health care and gun rights of West Virginians," said Morrisey for Senate spokesperson Nathan Brand. "Joe Manchin has a "D" rating from the NRA, and voted against President Trump's efforts to repeal and replace Obamacare. Lying liberal Joe has been wrong for West Virginia."

Manchin is a vulnerable Democrat this cycle and running for re-election in a deeply-red state that Trump overwhelmingly won by a huge margin in the 2016 presidential election. The conservative Democrat, who often walks a tightrope between the national party’s platform and appealing to conservative voters back home, is staunchly tethering his campaign to the issue he views most at stake for West Virginians: healthcare.

In a shift in tone from his 2010 campaign – during which he opted for a narrative that distanced his campaign from Washington Democrats and Obama’s signature piece of legislation – it appears as though Manchin is now not only embracing the health law, but also actively protecting it from his opponent.

"I'm more concerned right now about pre-existing conditions. I'm more concerned about 800,000 West Virginians losing their ability to have insurance or buy insurance because they've been sick. Something's wrong here, we've gotta change that," Manchin told ABC News in June.

In toeing that fine line, Manchin often boasted a relatively amicable relationship with President Donald Trump, even privately meeting with him at the White House, before Manchin voted against the tax bill.

But Trump has thrown his full support behind Morrisey.

"You're going to have a chance – you're going to have a chance to get a senator that's going to vote our program," Trump said in April during a roundtable on tax reform, which Morrisey attended. "Joe Manchin, he’s really not helped us."

Trump held a rally for Morrisey last month, hoping to precipitate support for the Republican candidate.

"He will fight for you like no one has ever fought for the people of West Virginia," Trump said of Morrisey, adding, "I like Joe, but Joe doesn't vote, he just doesn't vote for us."

This closely-watched Senate race is a toss-up, according to the Cook Political Report, and with Trump leaning in heavily to support Morrisey in his bid to unseat the Democrat, Manchin is locked in a tough fight as November nears.

ABC News’ Mariam Khan and Meridith McGraw contributed to this report.