A night of closely followed special elections and primaries in New York and Florida helps set the stage for a highly competitive November election.

In New York’s competitive 19th district, the Democratic nominee, Pat Ryan, defeated Republican Marc Molinaro in a special election in what could be one of the last bellwethers before November. The 19th was previously represented by Antonio Delgado, who was tapped to be lieutenant governor.

Mr. Ryan outperformed expectations, continuing the Democratic Party’s run of success in recent weeks. Polling ahead of the election suggested he would lose, with an August 22 Data for Progress poll showing Mr. Molinaro ahead by eight points.

The result comes as Democrats surge in national polling and following recent wins in special elections in Minnesota and Nebraska, and on the Kasnsas abortion rights ballot initiative.

In New York’s other special election, to replace Congressman Tom Reed in the 23rd district, Republican Joseph Sempolinski defeated Democrat Max Della Pia. 

Mr. Sempolinski will serve until January, when he will likely be replaced by the winner of the Republican primary in the district, the New York Republican Party chairman, Nick Langworthy.  He defeated businessman Carl Paladino, having garnered 52.1 percent of the vote at last count.

The primary marked a battle between the Republican establishment in the Empire State, represented by Mr. Langworthy, and the party’s more right-wing influences, represented by Mr. Paladino.

Mr. Langworthy threw his hat in the ring in what many saw as an attempt to prevent Mr. Paladino from securing the nomination, as Mr. Paladino was seen as a potential liability to New York Republicans after years of drawing negative attention from the national press — most recently for appearing to praise Adolf Hitler in an interview.

In New York’s 12th district, Congressman Jerrold Nadler defeated a longtime ally in Washington, Congresswoman Carolyn Maloney, likely marking the end of her 30-year career in the House. Both first took office in 1992, representing the old 10th and 12th districts, respectively.

This year’s redistricting drama pit Mr. Nadler against Ms. Maloney, and only one could go on to represent the new district, which combines Manhattan’s east and west sides.

In New York’s 10th district, an attorney who is heir to the Levi Strauss jean fortune, Daniel Goldman, clinched the Democratic nomination in a hotly contested race despite opposition from the party’s left flank.

With just more than a quarter of the vote, he defeated a congressman, Mondaire Jones, an assemblywoman, Yuh-Line Niou, and a city council member, Carlina Rivera. Progressives in the party were unable to unite around a candidate in opposition to Mr. Goldman.

Another progressive challenger lost in the primary in New York’s 17th district, with Congressman Sean Patrick Maloney defeating a state senator, Alessandra Biaggi. He becomes the quick general election favorite in the Democratic-leaning district.

The race was something of a proxy battle between mainstream and progressive Democrats, with Mr. Maloney enjoying the backing of the House speaker, Nancy Pelosi, and Ms. Biaggi supported by Congresswoman Alexandria Ocasio-Cortez.

In Florida, Congressman Charles Crist defeated the state agricultural commissioner, Nikki Fried, in the Democratic gubernatorial primary. Mr. Crist was widely seen as the favorite despite of some polling showing a last-minute surge in Ms. Fried’s favor.

Florida Democrats hope Mr. Crist will be their best chance to defeat Governor DeSantis, who did not face a primary challenger.

Facing off for the seat Mr. Crist left to run for governor, in  Florida’s 13th district, will be Republican Anna Luna against Democrat Kimberly Walker.

Congresswoman Val Demings, who was the Democratic favorite, will run against Senator Rubio in this November’s Senate election. Although it has largely flown under the radar, the Sun reports that it is shaping up to be one of the toughest races of Mr. Rubio’s career.