The mood was a sharp contrast with that for the previous nominee, Anthony Lake, who withdrew his name from contention, calling the process "a political circus."
The previous two nominees were rejected by parliament, resulting in months of delay in forming a new government.
His previous nominee for lieutenant governor, Stanford Morse, endorsed Williams.
President Hayes had promised not to run for a second term, and the previous Democratic nominee, Tilden, declined to run again due to poor health.
He is notable as the only brother of a previous nominee (William Jennings Bryan) to be nominated by a major party.
Tenet replaces the previous nominee, Tony Lake, who withdrew earlier in the week.
The committee's endorsement was not unanimous, as it had been for all three of President Reagan's previous nominees.
At the time, the 13 previous nominees for this Cabinet position won Senate confirmation in an average of eight days.
He added, "He said several times, 'I want to look at previous nominees who came before the committee, and what they were able to say."'
The previous nominee, businessman and educator Jack Ryan, removed himself from the race after damaging information from his divorce records were made public.