Although President Lyndon B. Johnson defeated Senator Eugene McCarthy in the non-binding presidential preference primary with 49% of the vote, McCarthy's superior organization allowed him to win twenty of the state's twenty-four pledged delegates; Johnson's poor performance in New Hampshire precipitated his decision not to run for re-election, which he announced on March 31.

Kennedy continued to demur, despite pressure from his aides to enter the race and worry that antiwar allies, like George McGovern, would begin to make commitments to McCarthy.

Trailing badly in national polls and with little chance to influence delegate selection absent primary wins, McCarthy decided to pour most of his resources into New Hampshire.

He was boosted by thousands of young college students who volunteered throughout the state, who shaved their beards and cut their hair to "Get Clean for Gene.

Despite his desire to oppose Johnson directly and the fear that McCarthy would split the antiwar vote, Kennedy pushed forward with his planned campaign.

By withdrawing, he could avoid the stigma of defeat and could keep control of the party machinery to support Vice President Hubert Humphrey.

[15] As the year developed, it also became clear that Johnson believed he could secure his place in the history books by ending the war before the election in November, which would give Humphrey the boost he would need to win.