(Bloomberg) -- Republicans took back the US House last year with the help of a significant turnout advantage, as Democrats — particularly Democratic women — actually failed to vote nationwide in the same numbers they did in the previous midterm election, according to a new analysis of voter data.

That analysis, released by the Pew Research Center Wednesday, cuts against one of the prevailing narratives of the 2022 midterm elections: That the Supreme Court’s decision overturning the nationwide right to an abortion energized women voters and held Republicans to a historically small majority in the House. 

Despite the decision, the Democratic advantage among women dropped from 18 percentage points in 2018 to just 3 points in 2022, with 51% of women voting Democratic and 48% for Republicans, according to Pew.

Turnout accounts for almost all of that shift. Of women who voted in 2018, 84% who voted Republican came back to vote in 2022, while only 76% of Democratic women did. 

Hannah Hartig, the senior researcher on the Pew study, acknowledged that the findings paint a more nuanced story of the 2022 elections. But she said the study doesn’t disprove the importance of the abortion issue, noting it’s impossible to know whether Republicans would have done even better among women without the Supreme Court’s decision. 

“We don’t have the counter-factual,” she said. 

The national study also obscures individual races where abortion rights were more threatened. In Pennsylvania, for example, exit polls showed that voters put abortion ahead of inflation on their list of concerns, defying the national trend. That helped Democrats install Josh Shapiro as governor and John Fetterman in the Senate. But in New York, where abortion rights have been guaranteed by state law since 1970, Republicans over-performed, winning six congressional districts where President Joe Biden won in 2020.

The Pew study underscores the importance of turnout in modern American elections. The party in control of the White House almost always suffers a turnout letdown in midterm election years, but the new data demonstrate how important turnout by urban, minority and women voters is to Democrats as the 2024 election approaches.  

That’s especially true as political polarization has resulted in fewer swing voters who can decide elections. Pew interviewed the same voters after the 2018 and 2022 elections and found that only 6% of women who voted Democratic in 2018 switched their vote to Republican in 2022, and 5% went the other direction.

“The thing our analysis reveals is how calcified the electorate is,” Hartig said. “That’s not to say that vote-switching or split-ticket voting isn’t consequential, but by and large voters are very loyal to their party.”

Still, the realignment of the parties continued, especially among rural voters: 7% of rural voters who supported Democrats in 2018 flipped their votes in 2022, while only 1% of Republicans went the other way. 

The analysis also confirmed the inroads Republicans have made among Hispanic voters, shrinking a 47-point Democratic advantage in 2018 to just 21 points last year.

The Pew study, based on interviews with 11,064 panelists, differs from traditional exit polls in two ways. The researchers use state voting records to confirm that the respondents actually voted, and they interview the same panelists in multiple elections, ensuring that any changes in opinion aren’t simply the result of interviewing different people. 

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