“I am not going to speculate what I would do in the Senate,” he told reporters in Los Angeles. “I’m a former vice president, I know what occurred in Ukraine, I know what occurred in terms of China, I know what occurred in terms of Russia. This is a president trying to get two of our most serious competitors, and not allies, to decide this election, to decide who he runs against.”

He added: “This guy, like all bullies, is a coward. He does not want to run against me.”