LaToya Cantrell, the first woman elected mayor of New Orleans, gives her acceptance speech to supporters at the Jazz Market in New Orleans, La. Saturday, Nov. 18, 2017.

Advocate staff photo by MATTHEW HINTON

Years from now, we'll likely look back on Mayor-elect LaToya Cantrell's huge win Saturday night as a turning point in New Orleans, the time when a new style of politics truly arrived.

For now, though, it's worth taking a moment to consider what it replaced.

Cantrell's whopping 20-point margin over Desiree Charbonnet, and the breadth of her support citywide, marked a remarkable rejection of some of the city's old rules, or the assumptions made by its political class, anyway.

It used to be that someone with Charbonnet's profile would have a built-in advantage. She's got generational family roots in the city, while Cantrell grew up in California. She's Creole, just like previous African-American mayors, and from downtown, where many black voters live. She had previously been elected citywide, although to offices that don't offer as high a public profile as Cantrell's district City Council seat. And she opened her campaign with what was clearly meant as a shock-and-awe show of strength, both with endorsements and with big campaign contributions.

Not only did it not propel her into the lead, it probably backfired. All that insider support, for someone with a good record as recorder of mortgages and municipal court judge but who was not well known in the electorate at large, raised alarms, and lent credence to outside attacks that the pigs were lining up at the trough.

Her team seemed caught off guard, but none of this should be surprising to longtime students of New Orleans politics.

The old rules have been losing their power for a while now. A revolt against patronage politics was one theme of the last election before Katrina upended everything. That was in the 2002 race to succeed Marc Morial, when Paulette Irons came on strong by promising to take the for sale sign off City Hall, tanked due to some personal issues, and ceded the reformist ground to a late entry named Ray Nagin. Ironically, many of the Irons's backers then were key players in Charbonnet's campaign now, and Nagin quickly backtracked on his campaign theme. But the concern has been apparent for quite a while now.

The influence of African-American organizations, which rose as black New Orleanians were finally gaining political power, has been waning too. LIFE hasn't been a juggernaut since Morial left town. The Progressive Democrats are kaput following a public corruption sweep that netted patriarch Bill Jefferson, the former congressman, and several of his siblings.

COUP, the political home of former Mayor Sidney Barthelemy and many Charbonnet die-hards, isn't going to scare anyone after Charbonnet's big loss. The one exception is BOLD, which elected longtime operative Jay Banks to the council. The group has close ties to Cantrell too, but given the scope of her victory, it can only claim a sliver of credit.

There's another irony here: About the only place where Charbonnet triumphed was Lakeview, home to a critical mass of white conservatives.

Instead of organizations, individual politicians have moved in to fill the growing void, but it was a bad season for them too. Chief among the losers was U.S. Rep. Cedric Richmond, who threw his weight behind not only Charbonnet but the two city council members who lost reelection bids, Nadine Ramsey and James Gray. His own position may not be in immediate danger — he still heads the Congressional Black Caucus, and it's not clear who'd run against him — but his days of being the city's principal kingmaker appear to be over.

Candidates might want to keep their distance from Leon Cannizzaro, too. The district attorney may have helped Charbonnet in those white areas, but he's way too divisive these days to help citywide. His presence at Charbonnet's side, amid the scandal over his office's fake subpoenas and other abuses, was likely a turnoff to at least some voters, particularly after he clumsily used his office to amplify Charbonnet opposition research on Cantrell's City Council credit card use.

This will likely be looked back upon as the election in which new forces replaced the old, when new and younger New Orleanians showed up in force, when voters voiced frustrations with an establishment that in many eyes has failed, when new technology overwhelmed older forms of voter communication, and when outdated ideas came up empty.

People will be reviewing Cantrell's win for years to come, to figure out what went right. Charbonnet's once-vaunted campaign, meanwhile, will go down as a case study of what went wrong.

Follow Stephanie Grace on Twitter, @stephgracela.