By Eric Beech and Moira Warburton

WASHINGTON (Reuters) -A New York Democrat who campaigned on abortion rights and the future of U.S. democracy won a special congressional election in a swing district on Tuesday, a victory that Democrats hope could signal a fundamental shift in national voter sentiment ahead of the November midterm elections.

Democrat Pat Ryan defeated Republican Marc Molinaro 51.3% to 48.7%, with 99% of the vote counted, Edison Research said, after a hard-fought contest for an open seat in New York’s 19th Congressional District, which spans part of the Hudson Valley and Catskill Mountains region and is known as a bellwether.

The election took on outsized national importance and became a testing ground for both parties’ campaign strategies. Ryan made the U.S. Supreme Court’s decision to overturn abortion rights a centerpiece of his campaign, mobilizing Democrats outraged by the ruling. Molinaro focused on crime and soaring inflation that voters say is their most pressing concern.

The district voted for Barack Obama in 2012, Donald Trump in 2016 and Joe Biden in 2020.

Ryan’s victory, coming after voters preserved abortion protections in Republican-dominated Kansas, will boost Democrats’ hopes that opposition to the Supreme Court ruling could help them to hold on to the House of Representatives and Senate in a tough election year.

Ryan will serve only until January, when the seat will disappear due to state redistricting. Both he and Molinaro are also running for different seats in the November midterms.

Voters also cast ballots in state primaries in New York, Florida, and Oklahoma to choose party nominees for the Nov. 8 elections, which will determine the balance of power in Congress in the run-up to the 2024 presidential election.

U.S. Representative Charlie Crist emerged as the Democrat who will try to unseat sitting Republican Governor Ron DeSantis in November.

Crist, 66, bested state Agriculture Commissioner Nikki Fried, Edison Research projected. With 78% of the vote counted, Crist had 59.1% vs. 35.4% for Fried.

Crist, who served as a Republican Florida governor from 2007 to 2011 before switching parties, portrayed himself as a candidate ready to unify the state after DeSantis’ focus on culture war issues. He drew endorsements from Democratic leaders including U.S. House Speaker Nancy Pelosi.

DeSantis is seen as a potential 2024 presidential candidate, and Democrats hope they can derail any White House bid by denying him reelection in Florida.

“When we defeat him on Nov. 8, that show is over,” Crist told cheering supporters.

Recent polling data shows DeSantis leading Crist by several percentage points. Running as a Democrat, Crist lost the 2014 governor’s race against Republican Rick Scott.

Meanwhile, Val Demings, another House Democrat, will square off against Republican Marco Rubio in Florida’s Senate race, after defeating three rivals in the state’s Democratic primary election, according to a projection by Edison Research.

Most opinion polls show Rubio leading Demings by several points to double digits, according to the tracking website FiveThirtyEight.com.

DeSantis and Rubio, a former presidential hopeful, had no primary opponents.

In a Republican Senate primary run-off in Oklahoma, U.S. Representative Markwayne Mullin beat former state House Speaker T.W. Shannon for the party nomination to replace retiring Senator Jim Inhofe, Edison projected. With 32% of the vote in, Edison said Mullin defeated Shannon by 66.6% to 33.4%.

SHOWDOWN OVER ABORTION

Democrats have been widely seen as the underdog party up to now in the midterm elections for House and Senate, with their prospects weighed down by historical trends, inflation, and President Joe Biden’s low job approval numbers.

Republicans are favored to take control of the House, putting them in a position to scupper Biden’s legislative agenda. But their chances of capturing the Senate have been cast into doubt by the weakness of Trump-endorsed candidates in the key swing states of Arizona, Georgia, Ohio, and Pennsylvania.

In recent weeks, Biden’s approval rating has recovered somewhat from its low of 36% to reach 41%, according to Reuters/Ipsos polling, as inflation has shown signs of easing and Democrats have celebrated a series of legislative wins in Congress.

The New York special election was the first competitive contest since the Supreme Court’s abortion ruling in June. But other special House elections in conservative districts in Nebraska and Minnesota saw Republicans prevail by much narrower margins than expected.

Also in New York, an unusual intraparty contest saw House Democrat Jerry Nadler defeat fellow Democratic incumbent Carolyn Maloney, ending her 30-year career in Congress in a redrawn district that pitted the two longtime politicians against each other.

Nadler, who chairs the House Judiciary Committee, won with 55.8% of the vote, vs. 24.2% for Maloney, who chairs the House Oversight Committee.

U.S. Representative Sean Patrick Maloney, a five-term Democratic incumbent, defeated challenger Alessandra Biaggi in a primary contest in suburban New York. With 48% of the vote counted, Maloney won 66.3% to Biaggi’s 33.1%, according to Edison Research.

The contest was seen as a proxy battle between the party establishment and its progressive wing. Biaggi was endorsed by Democratic Representative Alexandra Ocasio-Cortez, a leading House progressive.

(Reporting by Eric Beech and Moira Warburton; Writing by David Morgan; editing by Ross Colvin and Rosalba O’Brien)

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