Harris' election would defy history. Only 1 VP been elected prez since 1836

As Vice President Kamala Harris begins her fall campaign for the White House, she can look to history and hope for better luck than others in her position who have tried the same.

Since 1836, only one sitting vice president, George H.W. Bush in 1988, has been elected to the White House. Among those who tried and failed were Richard Nixon in 1960, Hubert Humphrey in 1968 and Al Gore in 2000. All three lost in narrow elections shaped by issues ranging from war and scandal to crime and the subtleties of televised debates. But two other factors proved crucial for each vice president: whether the incumbent president was well-liked and whether the president and vice president enjoyed a productive relationship.

You really do want those elements to come together, says Julian Zelizer, a professor of history and public affairs at Princeton University. If the person the vice president is working for is popular, that means people like what he's doing and you can gain from that. And you need to .