All three Mamdani-backed candidates won their races in the midterm elections on Tuesday, November 3, 2026, carrying New York City Mayor Zohran Mamdani's democratic socialist coalition from City Hall into the United States Congress. Brad Lander, Darializa Avila Chevalier and Claire Valdez each won a New York House seat, turning a clean sweep of June's Democratic primaries into three seats in the 120th Congress.

The victories were part of a much larger Democratic night, with the party taking control of both chambers of Congress and flipping at least four Senate seats, including contests in Republican strongholds such as Texas, Kansas and South Carolina. But the New York results carried their own significance: all three had first won primaries against established figures, confirming Mamdani as a Democratic power centre whose influence reaches beyond the five boroughs.

Key Points

• Brad Lander won New York's 10th District, beating Republican Jennifer Moore after defeating two-term incumbent Dan Goldman in the June primary.
• Darializa Avila Chevalier, 32, won the 13th District with 87.5 percent of the vote against Republican Jomo Williams (11.4 percent), after defeating Representative Adriano Espaillat in the primary.
• Claire Valdez won the open 7th District, beating Republican Melvin Rivera and succeeding retiring Representative Nydia Velazquez.
• Four other candidates linked to the Democratic Socialists of America also won House seats in the midterms.
• Governor Kathy Hochul was re-elected in New York, defeating Republican Bruce Blakeman.

What Happened

On Tuesday, November 3, 2026, voters in three heavily Democratic New York City districts sent the Mamdani slate to Washington. The results were never seriously in doubt: all three were considered shoo-ins after winning their primaries on June 23 in districts where Democrats hold commanding advantages. What mattered was the meaning — three candidates running openly as democratic socialists, each carrying Mamdani's endorsement, now hold seats in the House.

Lander, a former New York City comptroller, won the 10th District after defeating Goldman in a primary in which the war in the Middle East became a central issue. Lander opposed further United States military assistance to Israel, while Goldman was supported by pro-Israel groups including the American Israel Public Affairs Committee. Avila Chevalier's victory was the most emphatic of the three: the 32-year-old won the 13th District with 87.5 percent of the vote. A member of the Democratic Socialists of America, she had helped organise pro-Palestinian protests at Columbia University before defeating Espaillat, the chair of the Congressional Hispanic Caucus, in the primary.

Valdez completed the sweep in the 7th District, an open seat left by the retirement of Velazquez. She first defeated Antonio Reynoso in the primary, then beat Republican Melvin Rivera in the general election. Like Avila Chevalier, Valdez is a democratic socialist and a state Assembly member.

Background: How the Slate Was Built

The three wins were set in motion in June, when each candidate emerged from a primary that challenged established figures: Lander took on a sitting congressman, Avila Chevalier took on the chair of the Congressional Hispanic Caucus, and Valdez won a crowded contest for an open seat held for decades by Velazquez. Together, the June results established Mamdani as a Democratic power centre in New York. The expression "Mamdani-stan" has been used to describe the growing reach of the democratic socialist politics behind his rise, and Tuesday's results gave that phrase substance. The three winners campaigned on an agenda centred on working-class voters — housing, wages and the cost of living.

Mamdani-Backed Candidates Bring a Progressive Bloc to Congress

For Mamdani, the sweep does more than add three friendly votes in the House. It plants his coalition inside Congress at the moment Democrats regain control of both chambers, giving the mayor a direct channel into the party's national agenda. The three arrive with a shared political identity and a shared claim to have beaten the party establishment in open combat. The wins also test a question that has followed the democratic socialist movement for years: whether its politics can travel beyond deep-blue strongholds. Tuesday's answer, at least in New York, was that they can win primaries against entrenched incumbents and then hold the seats comfortably. The broader test will come in the 120th Congress, where the three will have to turn campaign promises into legislation.

Reactions: "It's Morning Again in America"

Mamdani marked the results with a brief post on social media. "It's morning again in America," he wrote, a nod to the scale of the Democratic wins across the country and to his own slate's sweep in New York. Senator Bernie Sanders described the results as "some of the greatest progressive victories in modern American history." Writing on Instagram, he said: "All across the country, in rural and urban areas, Americans said NO to oligarchy, and YES to an agenda that fights for the working class." His list of winners included Lander and Valdez among the House victors, alongside Senate and House candidates across the country.

Why It Matters

The sweep matters because it changes who speaks for New York in Washington. Lander, Avila Chevalier and Valdez replace or succeed figures associated with the party's centre: Goldman, a wealthy former prosecutor; Espaillat, a caucus chair; and Velazquez, a veteran of the House since 1993. Their arrival shifts the state's delegation leftward and gives the House's progressive bloc three new voices with direct ties to the mayor of the country's largest city. It also matters because of timing: Democrats enter the final two years of President Donald Trump's presidency holding both chambers, and the new members will vote on the investigations, spending bills and confirmations that define that period.

What Happens Next

The three winners will take their seats when the 120th Congress convenes in January, joining a Democratic majority in both the House and the Senate. Committee assignments are expected to be settled in the weeks after the new session opens, and the three New Yorkers will be pressing for seats on panels covering housing, labour, financial services and foreign affairs.

Frequently Asked Questions

Who are the three Mamdani-backed candidates who won?

Brad Lander, Darializa Avila Chevalier and Claire Valdez — democratic socialists endorsed by Mayor Zohran Mamdani — won House seats on November 3, 2026.

Which districts did they win?

Lander won New York's 10th District, Avila Chevalier won the 13th District with 87.5 percent of the vote, and Valdez won the open 7th District, succeeding retiring Representative Nydia Velazquez.

Did Mamdani endorse other winners?

The three New York winners were his endorsed slate, but the movement had a wider night: four other candidates linked to the Democratic Socialists of America also won House seats in the midterms.

What is the 120th Congress?

The 120th Congress is the next session of the United States Congress, taking office in January 2027, with Democrats controlling both the House and the Senate after flipping at least four Senate seats.

When do the new members take office?

They take their seats when the 120th Congress convenes in January 2027, serving two-year terms in the House of Representatives.

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