Hunter Biden, right, shown with his father, former Vice President Joe Biden, admitted on "Good Morning America" Tuesday his acceptance of a lucrative position on the board of a Ukrainian oil company was "poor judgment."

Democrat Joe Biden's presidential campaign machinery has been working overtime lately. While its public face was promoting its candidate, its private one has been in damage control.

The former vice president and his son, Hunter, claim they did nothing wrong during the Obama administration when the Democratic vice president was its point man on Ukraine and his son became a lucrative ($50,000-plus a month) board member of a Ukrainian natural gas company.

While the public face of the campaign, Biden, has been castigating President Donald Trump over a phone call to the Ukrainian president in which Trump invoked the Bidens and a potential investigation into their dealings in the country, its private one has been reading the voting public over the sordid mess.

What the campaign read was that the professions of innocence weren't playing, that the public wasn't accepting that the Ukraine deal was all on the up and up, whether it was or wasn't.

With U.S. Sen. Elizabeth Warren, D-Massachusetts, beginning to edge past Biden in some polls for the 2020 Democratic nomination and the next debate of top candidates Tuesday night, the campaign had to do something. It couldn't have Biden floundering on the subject if it were brought up.

So Hunter Biden appeared on ABC's "Good Morning America" Tuesday morning to say that accepting the gas company board position was, in retrospect, "poor judgment."

"I know I did nothing wrong at all," he said. "Was it poor judgment to be in the middle of something that is a swamp in many ways? Yeah."

The younger of Biden's two sons has been no stranger to poor judgment. He's had difficulties with alcohol and drugs that included stints in rehab and run-ins with the law. On one of the latter occasions, when a crack pipe was found in his rental car, he was serving on the board of the Ukrainian company, Burisma.

Hunter Biden's entree to the board came not too long after he was discharged from the Navy — after less than a year's enlistment — after testing positive for cocaine.

Before all that, he'd gotten a law degree, worked for MBNA, then a dominant issuer of credit cards in Delaware, then became a federal lobbyist but remained as a consultant for MBNA (when his father was derisively known as the senator from MBNA).

We won't detail the rest of Hunter Biden's career moves, but suffice it to say controversy has followed him in nearly everything he's done, from charges that he traded on his father's name in making deals for a private investment company to working with a Chinese private equity firm that invested in facial-recognition technology used to surveil China's Muslim population.

Unfortunately, the younger Biden likely has also felt he had to live up to his late older brother's reputation. Beau Biden, the son the elder Biden once referred to as his "soul," was to be his father's heir apparent. An attorney, he was a federal prosecutor, attorney general of Delaware and later joined the military first as a member of the Delaware National Guard and then as a major in the Judge Advocate General's Corps, during which his unit was deployed to Iraq. He was planning to run for governor of Delaware in 2016, but the cancer that was in remission during his 2014 announcement returned and claimed his life in 2015.

Hunter Biden isn't the first child to trade on his father's name — the Trump children seem to have no problem with it — and he's not the first to try to live up to the reputation of an older sibling.

But the public is having difficulty grasping that the younger Biden, with all his baggage, is the innocent one, and the president, whose phone call transcript with the Ukrainian president was released to the public, is the guilty one.

No, Hunter's "poor judgment" interview on "Good Morning America" was decidedly placed for two reasons. The first was that the campaign was tacitly admitting to the voting public that his supposedly perfectly innocent foreign dealings didn't pass the smell test, and the second was that the elder Biden would be able to answer any of his critics at the debate that his son has admitted that joining the gas company board was probably the wrong thing to do.

Yes, the younger Biden was throwing himself under the bus — carefully and with few injuries — for the good of his father's campaign. It won't stop all the questions, but the campaign hoped to staunch the internal bleeding.

Unfortunately for the former vice president, the more Trump's inelegant but hardly deadly phone call remains in the news — and that's what Democrats want to use to impeach him — the more the younger Biden's dealings remain in play.

We said last week we believe Joe Biden will have to be sacrificed by his fellow Democrats on the altar of impeachment, and while the "Good Morning America" appearance was meant to help we don't believe it's going to change things.