Anthony Weiner's sexting antics scuttled his own campaign to become mayor of New York City — and they may ultimately take down another front-runner, too.

Public Advocate Bill de Blasio has leapt to the front of the city's mayor's race with 30 percent of the Democratic primary vote, according to a Quinnipiac poll released Tuesday. City Council Speaker Christine Quinn comes in second with 24 percent, followed by former Comptroller Bill Thompson at 22 percent, and then Weiner way back at 10 percent.

The de Blasio surge is remarkable both for its size and for what it says about the race.

One month ago, de Blasio barely cracked 10 percent in most surveys. In the wake of Weiner's meltdown, his support has suddenly shot up — but Quinn's support has remained virtually unchanged.

That underscores the basic dynamic of the race as a choice between Quinn — Mayor Michael Bloomberg's ally on the City Council — and an anti-Quinn.

To many voters, Quinn is Bloomberg by a different name, and they see her candidacy as a continuation of his most controversial policies, like the city's stop-and-frisk police tactics. Weiner rose to the front of the pack as a Quinn alternative after declaring his candidacy, but his astounding free fall has opened the door for someone else to take that place.

That someone, for now, is de Blasio, whose camp made that very point following the survey's release.

Quinnipiac's survey further elucidates this dynamic in a couple of ways.

First, one-quarter of the Democratic primary voters surveyed say they would never, "under any circumstances," vote for Quinn. Just five percent feel the same of Thompson, and three percent say that of de Blasio. The only candidate more polarizing than Quinn is Weiner, whom a majority of voters say they would never support.

Second, in Quinnipiac's theoretical runoff scenarios (if no candidate cracks 40 percent there is an automatic matchup between the top two finishers) Quinn loses to both de Blasio and Thompson by double digits. De Blasio, the most liberal of the three, leads Quinn 54-38 percent, while Thompson leads her 51-41 percent.

Essentially, all the candidates not named "Quinn" are battling each other for the anti-Quinn vote. This is why de Blasio has called on Weiner to drop out, while Quinn has not: If Weiner stays in the race, he further splits that pool of votes.

However, as Weiner continues to plummet — mocking a British reporter's accent will do that to a campaign — it should benefit Quinn's rivals at her expense. At this point, it's no longer a given that Quinn will even make it to a runoff.

Some caveats: It is just one poll. Furthermore, Quinn has the kind of establishment support that could prove crucial on Election Day. Still, Quinn is certainly in for a period of second-guessing: