How do you distinguish yourself in a field of nine Republican candidates for Pennsylvania governor?

Lou Barletta is running as the former congressman and Donald Trump ally GOP voters know and trust. Dave White casts himself as a blue-collar businessman who can shake up Harrisburg. Doug Mastriano says he’s the true grassroots candidate. They all have one thing in common: They either currently or previously held elected office, meaning they’ve taken votes that are ripe for political attacks.

So Bill McSwain, the former U.S. attorney running as a “conservative outsider,” is trying to take advantage of that.

“Stop gambling with career politicians,” the narrator says in a new McSwain campaign TV ad.

It’s the first TV attack ad of the race and comes just six weeks before the May 17 primary election. Mastriano and Barletta have consistently led in polls of Republican voters, even as McSwain, White, and state Senate leader Jake Corman spend millions of dollars on the airwaves.

» READ MORE: Bill McSwain was ‘angling to run for something’ as U.S. attorney. Now his run for governor is all about his time as a prosecutor.

In the ad, Mastriano’s, Barletta’s, and White’s faces are seen on a slot machine. The ad notes that White, a former Delaware County councilman, voted to raise property taxes. It targets Mastriano for his vote in favor of the “unconstitutional mail-in voting law” — a reference to the 2019 election overhaul known as Act 77 that passed with bipartisan support before coming under GOP attack in the lead-up to and after the 2020 election. A state appeals judge called the law unconstitutional earlier this year, but the state Supreme Court stayed that ruling until it issues its own.

Barletta’s apostasy? He “approved Obama’s budgets” as a congressman, the ad says.

The spot goes on to highlight McSwain’s background as a “Trump-appointed prosecutor” who has “never run for office and will permanently cut the gas tax.”

Left out is any mention of Corman. That would seem to indicate McSwain’s team isn’t worried about him.

» READ MORE: Fact-checking Bill McSwain’s campaign ads and statements as he runs for Pennsylvania governor

White’s campaign called the ad a sign that McSwain is flailing. White campaign manager Bob Salera called McSwain “the handpicked puppet of Trump impeacher Pat Toomey” — echoing criticism lobbed by a pro-Barletta super PAC.

“And after spending nearly $6 million of his billionaire sugar daddy’s money to try and prop up his imploding candidacy, McSwain hasn’t moved an inch in the polls,” Salera said, referring to support from a political group primarily bankrolled by billionaire businessman Jeffrey Yass.

The group, Commonwealth Leaders Fund, made $5.9 million in in-kind contributions to McSwain’s campaign, according to records filed Tuesday. Commonwealth Leaders Fund has bankrolled most of the pro-McSwain ads, but the latest one was paid for by McSwain’s campaign itself.

Barletta adviser Tim Murtaugh said: “Republicans are looking for a tested and trusted conservative leader to be our next governor. That’s Lou Barletta.”

McSwain reported raising $1.4 million during the three-month period ending March 28. He spent about $546,000 and had about $1.7 million in the bank.