Curtis Sliwa put up a spirited fight in the mayoral race, bringing his characteristic energy and flair to the campaign trail. Yet, the outcome was never really in question. Both Sliwa and the public were well aware that victory was out of reach for him.

As the founder of the Guardian Angels, Sliwa stepped up as the Republican candidate largely because no one else was willing to take on the challenge. The absence of any formidable contenders from the GOP highlighted a significant oversight on their part.

This oversight proved costly. In an unexpected political landscape, with the possibility of a three-way race, the Republicans missed a golden opportunity to potentially reclaim City Hall. Ultimately, that chance slipped through their fingers.

Failing to find another candidate turned out to be a mistake for the GOP. A big one.

In a three-way race no one could have expected, Republicans had a crack at recapturing City Hall. Didn’t happen.

The party was caught off guard. Republicans blew an opportunity that historically arises only about once every quarter-century.

Four years ago, to some fanfare, Republicans vowed to find a top-tier nominee for mayor in 2025 after getting blown out by a weak Eric Adams.

A wealthy business leader or a crime-fighter perhaps. Maybe a turnaround expert.

Everyone had an idea, but nobody had a candidate — even with the “free” millions coming from New York City’s profligate candidate matching-funds ­program.

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Populist appeal

It’s a crying shame because the five boroughs are winnable for the GOP, even more so today, theoretically, than when Republican Mayors Rudy Giuliani and Mike Bloomberg captured four of five boroughs in their respective ’97 and ’05 re-elections.

For better or for worse, today’s GOP is more populist than its earlier iterations. It appeals far more to immigrant and working-class communities than the party of Reagan and both Bushes did.

That’s been showing up in tangible ways in ethnic enclaves across the five boroughs.

Eastern Europeans, Asians and Hispanics are increasingly voting Republican. Orthodox Jews are now semi-reliable GOP voters, and many secular Jews may never fully trust the Democratic Party again after it anointed an emphatically anti-Israel standard-bearer for mayor.

In short, New York’s long-standing ethnic political silos are beginning to crumble.

The key to Republicans winning statewide in New York is to win around 32% of the city vote. Former Rep. Lee Zeldin hit the 30% threshold in 2022 and fell just short.

A couple more points out of the boroughs and a Gov. Zeldin would be preparing for re-election right now.

The Republican candidate for New York governor next year, be it Rep. Elise Stefanik, Nassau County Executive Bruce Blakeman, or some dark horse out of nowhere, must have a five-borough candidate strategy.

Indeed, they should start with a five-borough strategy. It will determine more than half the statewide vote.

The party with the energy and presence on the streets of the city is the party that will attract new or crossover voters.

Right now in New York that energy is on the far left. The Working Families Party and the Democratic Socialists of America are smart, organized and well-funded.

To them, politics is everything. It’s year-round.

Republicans need to counteract them with their own energy — and then double it.

Republican Gov. George Pataki understood that. He won three statewide terms from this strategy in part. He always sought converts.

Conspicuous, year-round GOP headquarters of the type Pataki instituted in Washington Heights and elsewhere are needed in Flushing, Brighton Beach and everywhere in between now.

There is opportunity in every community. Republicans can ignore none of them. (Bloomberg won nearly half the city’s black vote in ’05.)

County cooperation

This begins at the county level.

Each borough — Kings, Queens, Richmond, New York and The Bronx — has a GOP chairman and committee in charge of developing candidates. The nods of three of five are needed to anoint a mayoral nominee.

Too often these committees work as individual fiefdoms.

It’s no one’s fault. Happens naturally. Brooklyn does Brooklyn, Manhattan does Manhattan, and in the end there’s a scramble.

But if Republicans are to win statewide in 2026 and citywide in 2029, those chairs need to start working together now.

They need to develop a strategy, along with the Republican State Committee, to maximize a voting trend already in motion.

Everyday resources must go where opportunity is greatest: the Asian, Latino and Jewish communities for starters.

Anti-biz backlash

The GOP should also increase its outreach to the New York City business community.

It’s been owned by the Democrats for decades, but Zohran Mamdani’s radical, anti-business candidacy should have put that relationship in jeopardy.

The GOP should exploit the breach.

The biggest prize imaginable is available if they succeed: If New York Republicans can begin reliably winning 32% of the city vote every four years — Bloomberg scored 58% in ’05 — New York would no longer be a flyover state.

Imagine that.

We would actually have a say again in presidential elections, not to mention US Senate elections, like one presumably featuring a weak Chuck Schumer in 2028.

The state that once boasted 47 electoral votes, and that has now atrophied to 28, would again have leverage.

A state in play is a state that gets resources from Washington.

I’m genuinely grateful that Curtis Sliwa stepped forward to run again. May it be his last race, though.

Republicans deserve a chance to win. We didn’t get one this time.

William F.B. O’Reilly is a New York-based Republican consultant and a former Newsday columnist.