Pat Brown had presidential ambitions, and certainly vice presidential ambitions by 1964. He suspected Johnson may have chose him as his running mate. When Johnson called leading up to the convention, Brown suspected it was going to be a formal request for Brown to be his running mate. It turned out that Johnson wanted Brown to introduce him to the convention, and the vice presidential candidate was not also going to introduce the president, so Brown quickly realized he was not going to be running with Johnson.
What if Johnson had asked Brown to be his running mate in 1964?