Robert F. Kennedy 1968 presidential campaign
The Robert F. Kennedy presidential campaign began on March 16, 1968, when Kennedy, a United States Senator from New York, mounted an unlikely challenge to incumbent Democratic United States President Lyndon B. Johnson. Following a near-upset in the New Hampshire primary, Johnson announced on March 31 that he would not seek re-election to a second full term.
Source: Wikipedia — Robert F. Kennedy 1968 presidential campaign (CC BY-SA 4.0)