Which Donald Trump will show up at Thursday night's CNN Presidential Debate?

It's the biggest question surrounding Thursday night's CNN Presidential Debate, which is the first of two on-stage showdowns between President Biden and former President Trump in the 2024 election rematch.

Which version of the former president will show up at the prime-time debate in Atlanta, the capital and largest city in the southeastern battleground of Georgia?

Will it be the undisciplined candidate who continuously interrupted Biden and debate moderator Chris Wallace dozens and dozens of times at their first debate in the 2020 election?

Trump appeared to lose his cool, failed to condemn white supremacists, and his performance was widely panned by political pundits and viewers alike.

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The then-president re-worked his strategy and his disciplined and measured performance in the second 2020 general election debate was a vast improvement. But it was too late, as Biden ended up winning the presidential election.

"If he replicates that performance, Donald Trump’s going to have a very good night," longtime Republican consultant and veteran debate coach Brett O'Donnell told Fox News.

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O'Donnell said his advice to Trump is "watch the second debate you had with Joe Biden in 2020 and replicate that performance. Watch it over and over and replicate that performance in this debate."

"He was measured but firm," O'Donnell said of Trump. "You can be aggressive and passionate without being offensive."

O'Donnell knows a bit about coaching presidential candidates ahead of their debates. He assisted in debate preparations for George W. Bush in 2004, GOP presidential nominee Sen. John