Mr Prendergast was yesterday voted back for a second term on the Mosgiel-Taieri Community Board by 0.1736 of a vote.
That followed preliminary results on Saturday that showed Mr Prendergast on 850 votes, just one vote behind Mark Willis on 851.
It emerged then the final result would not be known until later this week when special votes were counted.
Special votes can come from those on the unpublished roll, who changed their address, had not received voting papers or may have messed up their vote or lost or destroyed their papers.
Those votes were counted this week, and yesterday Mr Prendergast was confirmed as a winner on the tightest of margins.
He put the unusual result down to "good old STV [single transferable voting]".
He said STV was "the most perverse" procedure where nobody understood what was going on.
"It’s absurd."
Mr Prendergast was a city councillor and community board member for 24 years until 2007, when he lost his seat to Cr Kate Wilson.
After six years out of politics, he stood and was elected to the community board in 2013.
"Given my age it’s not easy to establish a sense of purpose," the 76-year-old joked.
"I can’t shear sheep or dig fencepost holes any more."
He did, however, have institutional knowledge about local government process he was keen to again bring to the community board.
There were no changes on the other Dunedin community board where the vote was tight, the Strath-Taieri Community Board.
In the Queenstown-Lakes district the inclusion of special votes did not change the outcome in the Wanaka Community Board election, where there had been a narrow margin between the fourth-highest polling candidate Ruth Harrison, and fifth-highest, Brian Lloyd, the board deputy chairman last term.
