"Apparently he had my speech on Air Force One," Biden said at about the same time, 250 miles away in Mount Pleasant, Iowa. "I think he's really fascinated by me, I find it fascinating."
It was a political version of the putdown preferred by passive-aggressive teenagers everywhere – why are you so obsessed with me? – rendered by two Septuagenarians eager to occupy the other's head.
In the end, it was Biden who named Trump 35 times more frequently by name, according to CNN census, compared to 15 mentions of Biden by the president.
Nevertheless, the reasons for the obsession for both men who competed in Iowa on Tuesday, but never crossed, are numerous and obvious.
Trump has exposed Biden as the biggest threat to the blue ̵
This comes to Trump's continued fixation with his predecessor, President Barack, on Obama and the connection to this government that Biden represents.
Meanwhile, Biden has focused his entire election campaign on the serious need to defeat the President. Unlike some of his Democratic rivals, who stayed on the sidelines as midfielders on Tuesday, Biden has decided to focus on Trump, though he confidently says he will not be involved in a mud strike.
Employment with the incumbent has given his election campaign a general sensibility that matches the image of a front-runner he desperately wants to represent.