If the Democratic Party’s 70-year streak holds in Philadelphia, the winner of today’s primary will be its next mayor because — despite lambasting big cities as hellscapes — few Republicans are willing to make a case for change in big cities.

“Nationally,” the Republican candidate for mayor of Philadelphia, David Oh, told me, “Republicans have been looking at the knockout blow — win the presidency, the Senate — and I think what they’ve failed to do is understand the importance of the jab.” 

In a strategy that dooms Republican chances to win Pennsylvania’s electoral votes in presidential races, Mr. Oh said the party has sought to “draw an imaginary border between ourselves and Philadelphia, the most populated county in our state.” 

Although Mr. Oh is making the fight, he was opposed by the city’s Republican Party, something that may now help the U.S. Army veteran, former councilman at-large, and prosecutor as he seeks to attract Democrats and the city’s independents, which equal the share of registered Republicans. 

Mr. Oh tells me he is “presenting to people that no matter how much you hate the Republican Party, sometimes the people from that party will do a better job than the people from the Democratic Party. Sometimes change will not come from anybody within the Democratic Party. It will come from an outsider, a Republican that will make your life better.”

Yet over the past 50 years, Republicans have ceded America’s urban centers, which manifests in lopsided voter registration advantages of seven-to-one in Philadelphia and New York City, leading to one-party rule.

The results have been predictable as the modern heirs to Tammany Hall’s Democratic sachems know that no matter how much they fail to deliver, they will still hold onto power, patronage, and prestige.

 Demographic numbers scare off Republican candidates, donors, and press while quality-of-life on issues like crime and taxes drive Democratic voters into Republican strongholds. It’s a self-defeating cycle, one that many on the right have long thought would redound to their benefit if they just waited. 

Victory, however, favors the bold, as Mr. Oh appears to realize. Abandoning big cities except for fundraising trips isn’t a recipe for success, nor is embracing the idea that they’re free from responsibility as America’s alabaster skylines crumble.

Offering up sacrificial lambs for office and paving their way for book deals, podcasts, and TV gigs after a great concession speech does nothing to win hearts and minds, nor does it help alleviate the suffering of fellow citizens.

Mr. Oh’s campaign runs contrary to GOP surrender of the type Ambrose Bierce wrote about in “The Devil’s Dictionary.” Describing the ancient Persian doctrine of Manichaeism, “the incessant warfare between Good and Evil,” he said, “When Good gave up the fight, the Persians joined the victorious Opposition.”

Calling Democrats evil won’t win many votes, but Republicans have allowed themselves to be painted as agents of darkness in cities. Even when a Republican in Los Angeles, Rick Caruso, joined the victorious opposition by switching his affiliation for the 2022 mayoral contest, he went down to defeat by seven points.

As I wrote in the Sun two months ago, rather than fight for urban centers, the GOP chooses to redefine victory as the defeat of leftist candidates like Chicago’s Democratic mayor, Lori Lightfoot, or of the more left-wing opponents of New York City’s mayor, Eric Adams.

“Lost in their euphoria,” I wrote after Ms. Lightfoot’s defeat, “is the fact that another Democrat will fill her shoes and Republicans failed to even field a candidate for her seat.” 

The only definition of winning is getting more votes, something only one GOP presidential hopeful has done in the past 30 years, and “nationwide,” as I wrote in the Sun last November, “Democrats hold a registration advantage” of 11.6 million voters over Republicans.

Republicans may not start running big cities any time soon, but as Woody Allen said, “eighty percent of success is showing up,” and if the party believes in the strength of their ideas, showing up in the ring to land some jabs — and to offer voters a choice — is the first step to building a sustained national majority.