Ukraine was bound to come up in Tuesday's Democratic debate at some point, but when it did, it quickly became clear that neither former Vice President Joe Biden, nor his primary opponents, wanted to focus on it.

With the debate's second question, Biden was given a chance to address the unfounded allegations lobbed by President Trump: that Biden used his federal power to corruptly favor a Ukrainian gas company that was paying his son, Hunter.

Even in asking the question, however, CNN's Anderson Cooper noted that there is "no evidence of wrongdoing" to support Trump's assertions.

"My son did nothing wrong. I did nothing wrong," Biden said, before shifting the focus to talking about "why it's so important to remove" Trump from office.

"He knows if I get the nomination, I will beat him like a drum," Biden said.

The former vice president said he never discussed anything about Ukraine with his son, who was paid as much as $50,000 a month while serving on the board of the country's largest gas company, Burisma.

Trump has tried to draw a line between Joe Biden's push as vice president to remove Ukraine's top prosecutor, Viktor Shokin, saying that the decision was made to protect Burisma, which had previously been under investigation by Shokin.

In reality, the decision to remove Shokin was in keeping with U.S. policy at the time, and consistent with the goals of European allies and the International Monetary Fund.

Hunter Biden spoke about the issue Tuesday morning in an interview with ABC News, saying his involvement with Burisma was, in retrospect, "poor judgement on my part."

"Did I make a mistake? Well, maybe in the grand scheme of things, yeah," Hunter Biden said. "But did I make a mistake based upon some ethical lapse? Absolutely not."

On Sunday, he released a statement in which he said he will forgo foreign business deals if his father is elected president.

"My son made a judgment. I'm proud of the judgement he made," Biden said. "And let's focus on this. The fact of the matter is that this is about Trump's corruption. That's what we should be focusing on."

Other candidates on stage also seemed to want to move on from Ukraine, despite Biden's position as one of the campaign's front-runners.

During the back and forth between Biden and CNN's Cooper, Sen. Cory Booker, D-N.J., could be heard trying to inject to object to the questioning.

Sen. Bernie Sanders was given a chance to respond immediately after Biden's response, but instead shifted focus to climate change and health care.

"We cannot and must not turn our backs on the pains of the middle class," Sanders said.

Later on, before answering another unrelated question, Sen. Booker returned to the Ukraine question.

"That was so offensive, he should not have to defend himself," Booker said, who added that the controversy reminded him of the Hillary Clinton email scandal of 2016, which was fueled in part by a number of unsubstantiated claims by Trump and his surrogates.

Using the second question of a nationally televised debate to focus on debunked accusations was wrong, according to Booker, and not beneficial to voters.

"The only person at home enjoying that was Donald Trump," Booker said.

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