Congressman Anthony Weiner, a probable mayoral candidate, showed yesterday that if he does run, he’s going to campaign against Mayor Bloomberg’s fiscal record over the past eight years — and boy, does Weiner have a lot of material.

Most startling, though, was not Weiner’s criticism of things like the mayor’s having amassed huge amounts of debt, his higher spending, and his having expanded the city payroll by the equivalent of “the entirety of Middle Village, Queens, to work full time for the city.”

These are just the facts. The surprise was that Weiner is the first mainstream candidate for office to offer this prediction about the lavish benefits that municipal employees enjoy: “Whether it’s five years down the road or 10 years down the road, the days of having a guaranteed, defined-benefit pension are probably not going to be around much longer.”

As noted here Sunday, it’s true that Weiner is just saying something that’s quickly becoming mainstream thinking in New York. It is becoming obviously unconscionable that public employees can expect free health benefits and, after a relatively few years of work, guaranteed high pensions for life, all paid for by private-sector taxpayers who can expect no comparable benefits.

But while regular New Yorkers may grasp this disconnect from reality, the city’s public-sector unions and their supporters are way behind the times.

And when it comes to actions that encourage this continued disconnection, the pols in power have only coddled the public workforce. Witness Bloomberg’s bizarre awards of 4 percent annual raises long-term to the municipal workforce last year, with no concessions, even as the extent of the city’s economic woes had become clear.

Weiner could have easily convinced himself that the safest thing, politically, to try to win back some of that union support from Bloomberg was to say nothing at all — but he didn’t.

The disconnect between regular (non-municipal-employee) voters and the insider special interests is reminiscent of the pre-Giuliani days, when normal people understood full well that it wasn’t acceptable to fear street crime and demanded a change, but the politicos were full of excuses as to why nothing could ever change.

Back then, Giuliani bucked the conventional wisdom and made New York safer.

In doing so, he gave the next mayor an opportunity to fix less obvious problems in the city that are just as harmful, long-term, to New York’s future, most obviously its profligate spending.

But that next mayor didn’t take that opportunity, instead making the problem much, much worse.

There’s still an opportunity, then, for a newcomer to show that just as New York was never ungovernable, neither is its budget.