The supervisors considered nominating either City Administrator Ed Lee or Sheriff Michael Hennessey to serve as interim mayor, but postponed taking a vote until Friday.
There was vociferous debate between the board's progressive and moderate factions. The progressives nominated Hennessey, and Lee was chosen by the moderates.
Just as it appeared likely that Lee had the six votes necessary to be nominated, several progressive board members requested a continuance until Friday in order for them to have time to speak with Lee about the appointment.
The postponement came after Daly said some sharp words during the meeting. He lashed out at David Chiu saying, "I will haunt you. I will politically haunt you... for the biggest fumble in San Francisco politics. It's on like Donkey Kong." His tirade continued saying, "We're about to witness the biggest fumble in the history of progressive politics in San Francisco."
Daly also taunted Michaela Alioto-Pier when she commended Dufty's pick and kept repeating, "You represent the rich." Then Alioto-Pier talked about bringing in help from the sheriff, but he was ironically the other top candidate and was also sitting in the room. Daly said, "Call the sheriff. He's right there. There's the sheriff."
Daly stormed out and a recess was called. Later to the media Daly said, "I acted with righteous indignation. Basically, I've served for 10 years as the whip in the progressive political camp and tonight I whooped some ass."
A special meeting of the board is now scheduled for Friday at 3 p.m. at City Hall.
Four of the lawmakers that make up the board have been termed out of office: Alioto-Pier, Sophie Maxwell, Bevan Dufty and Daly.
"In the last 10 years we've opened the doors to City Hall," said Daly earlier on in the day.
On Saturday, new members take their place. So this was perhaps the last, best chance for these lawmakers to make what one called their most important decision ever -- picking an interim mayor to replace Newsom.
The supervisors have wrangled with this issue for some time, but they can't get a majority of the 11 board members to agree on a candidate.
And there's a hitch. Newsom is still in office and he is delaying his swearing-in as lieutenant governor because he wants the new board, which will presumably be more moderate, to choose. Newsom believes he can delay heading to Sacramento and cites Article 20 of the California Constitution which says an elected official doesn't assume office until they take the oath of office, and that they "shall, before they enter upon the duties of their respective offices, take and subscribe the... oath."
But ABC7 legal analyst Dean Johnson doesn't agree with Newsom's interpretation.
"If I'm the judge ruling on this case, my ruling is Gavin Newsom is now lieutenant governor of the state of California, to coin a phrase, whether he likes it or not," said Johnson.
The mayor's office signaled that Newsom would be satisfied with either Lee or Hennessey as interim mayor. Newsom has called for a mayor that would not seek higher office and would guide the city through this year's budget difficulties until the next mayoral election, which takes place in November.
Progressives have seen the appointment as an opportunity to replace the moderate Newsom with someone more to their liking.
The Associated Press contributed to this report