In New York Win, Democrats Sense a Pivot on Immigration and Border Politics

A victory in a New York special election on Tuesday injected Democrats with fresh optimism that the party might have found some of the basic ingredients to neutralize immigration and the border as political issues, which party officials have privately seen as among their deepest areas of vulnerability in 2024.

The success in the race for a House seat by former and now future Representative Tom Suozzi — a Democrat whom Republicans had pilloried as “Sanctuary Suozzi” — came in a corner of the country, Long Island, that had been increasingly hostile to Democrats in the last two years. And Mr. Suozzi won after he frontally and repeatedly addressed a topic that his party has sometimes tried to shy away from.

With border crossings surging to record highs in recent months and more than 170,000 migrants arriving in New York City, Republicans had hoped to use immigration to paint Mr. Suozzi as unacceptably beyond the mainstream. The leading G.O.P. super PAC spent roughly $3 million on two television ads that said Mr. Suozzi had “rolled out the red carpet for illegal immigrants.”

But in the final 10 days of the race, an analysis from AdImpact, the media-tracking firm, showed that Democrats were actually airing more ads than Republicans on immigration, with Mr. Suozzi’s campaign running clips of an appearance he once made on Fox News in which he was introduced as “one of the Democrats” backing I.C.E., the immigration enforcement agency.

Mr. Suozzi’s victory came only days after congressional Republicans had torpedoed bipartisan legislation on Capitol Hill that would have cracked down on unlawful migration across the border with Mexico. Donald J. Trump, the front-runner for the Republican presidential nomination, had lobbied