Hubert Humphrey.
Humphrey entered the race too late to participate in any primaries, and relied on "favorite son" candidates to help him win delegates. He also lobbied for endorsements from powerful bosses within the DEMOCRAT Party, which provided him with necessary delegates.
This traditional approach was criticized by the other candidates, who hoped to win the nomination from popular support.
Robert Kennedy was assassinated in June 1968, leaving McCarthy as his only opponent, until the 1968 DEMOCRAT National Convention, when United States Senator George McGovern of South Dakota ran as the successor of Kennedy.
Humphrey won the party's nomination at the Convention on the first ballot, amid riots in Chicago.
https://en.wikipedia.org/wiki/Hubert_Humphrey_1968_presidential_campaign
rules have changed a lot since then. hell the way they do super delegates now vs. 4 years ago is different

