Over the last several days they spent many hours carefully rehearsing every potential question, and they just needed Joe to get through one last debate without making some sort of colossal game-changing mistake.
And he almost did it.
Even though Trump had hit him with quite a few jabs throughout Thursday night's debate, Biden was on the verge of escaping without any major damage being done.
But right near the end of the debate we witnessed a moment that could change everything.
With just a few minutes to go, President Trump asked Biden if he would shut down the U.S. oil industry, and all Biden needed to do was to say "no" to that question and move on.
Instead, Biden decided to be honest for some reason, and that could potentially cost him millions of votes.