• Donald Trump is promoting an array of products, including Bibles, sneakers and perfume, while he runs against President Joe Biden.
• Trump's business activity on the campaign trail is unprecedented, experts say.
• As the Biden campaign extends its fundraising lead over Trump's political operation, the GOP nominee has said he "might" put his own money into the race. He did not do so in 2020.

Sneakers. Perfume. Trading cards. Bibles.

Those are just some of the products Donald Trump is hawking while he runs to unseat President Joe Biden.

They join a sprawling catalog of Trump-branded merchandise, ranging from steaks to scented candles, that the businessman-turned-president has licensed over the years.

But as his campaign coffers dwindle and his fortune comes under threat, Trump — who has never completely severed his political career from his financial one — is now actively intertwining his business ventures with his White House bid.

"There is no precedent for this level" of business activity during a presidential campaign, Harvard Law School Professor Lawrence Lessig told CNBC, though "the trend has been building for many years."

Brendan Fischer, deputy executive director of money-in-politics watchdog Documented, agreed.

"I can't think of any other modern example of a presidential candidate hawking an array of goods for their private benefit," Fischer said.

For an average candidate, that activity might trigger a campaign finance investigation — but it likely won't for Trump, who has been selling branded goods long before he entered politics, according to Fischer.

"Trump is a unique case," he said.

That uniqueness was on full display Tuesday, as Trump unveiled his latest promotion: a $60 Bible that includes copies of the nation's founding documents, along with lyrics from country star Lee Greenwood's hit song, "God Bless the U.S.A."

The song by Greenwood, who is partnering with Trump to endorse the high-priced holy book, is a regular needle drop at the presumptive Republican nominee's campaign rallies.

Trump made the campaign connection even more explicit in a video announcing the promotion, warning that Americans' rights are under threat and declaring, "we're gonna get it turned around." He also invoked his campaign slogan, "Make America Great Again," multiple times.

It is unclear how much money Trump is making off the Bible — he is receiving royalties from its sales, a person familiar with the arrangement told The New York Times — but whatever he gets will be effectively going into his pocket.

The website for the Bibles says it has no link to Trump's campaign. It instead uses Trump's name, likeness and image under paid license from a company called CIC Ventures LLC.

Trump's 2023 financial disclosure calls him the "Manager, President, Secretary, & Treasurer" of CIC Ventures, and lists his revocable trust as the sole owner of the company. Trump has made more than $5 million in speaking engagements through the company, the disclosure shows. Florida business records show CIC's address is the same as Trump's golf club in West Palm Beach, Florida.

Lessig noted that Trump's business moves do not appear to be violating campaign ethics or financial rules.

"I don't think there's any ethical problem with it at all — so long as the proper reporting requirements are complied with," the professor said.

"There may well be a strategic or brand problem with it, but that's the same as with any political speech," he added.

Trump campaign spokesman Steven Cheung told CNBC, "These successful business deals are completely separate from the campaign."

Trump's Biblical endorsement came during Holy Week, the run-up to Easter and a sacred time for Christians. It also came less than six weeks after Trump traveled to a sneaker convention in Philadelphia to launch his own line of tennis shoes.

The aptly titled Trump Sneakers range in price from $199 up to $399 to preorder. Two of the available styles are decorated with the number 45, a reference to Trump's tenure as the 45th U.S. president.

That website selling the sneakers also advertises Trump-branded "Victory47" cologne and perfume, both of which cost $99.

"'Victory' is the signature scent of strength and success, encased in a luxurious gold bottle," the site's description of the cologne reads.

Trump's appearance at the convention further blurred the line between campaign outreach and capitalist enterprise.

"We're going to turn this country around fast. We're going to turn it around. And we're going to remember the young people, and we're going to remember Sneaker Con," he told the crowd, which greeted him with a mix of cheers and boos.

The sneaker site says that "Trump" and its associated design are trademarks of CIC Ventures, and it notes that Trump has licensed his name and likeness to a company called 45Footwear LLC. That firm is reportedly registered in Wyoming, one of the cheapest places in the country to start a business.

The shoes are not designed, made or distributed by Trump or the Trump Organization, according to the site.

As the Biden campaign extends its fundraising lead over Trump's political operation, the GOP nominee has said he "might" put his own money into the race. He did not do so in 2020.

Trump also has just days to post a $175 million appeal bond to pause the state of New York from collecting on a $454 million civil fraud judgment against him. He already put up a $91.6 million bond as he appeals a separate civil case where he was found liable of defaming writer E. Jean Carroll.

Trump also faces 91 criminal charges in four separate courts, with his first trial set for April 15. Trump has spent more than $100 million on his legal fees since leaving office in 2021, though none of it has come from his own pocket, according to The New York Times.