Pennsylvania has new state House and Senate maps.

The districts are redrawn every 10 years to reflect population changes, and new boundaries were approved Friday by a five-member commission. Those maps now become official until the next decennial redistricting after the 2030 census — though Friday’s vote did kick off a 30-day window in which anyone can file appeals with the state Supreme Court.

Pennsylvania has 50 Senate districts and 203 House districts. How they are drawn — including which voters from each party, racial and ethnic communities, and local economic, social, and cultural interests are grouped together or divided — will help determine control of the legislature, and shape political power and representation for a decade.

The new maps still slightly favor Republicans but are significantly closer to evenly split than the current maps, according to a detailed data analysis conducted for The Inquirer by the nonpartisan Princeton Gerrymandering Project. For example, 94 of the current House districts voted for Joe Biden in 2020 and 109 voted for Trump, despite Biden narrowly winning Pennsylvania. In the new map, 103 districts voted for Biden and 100 for Trump.

The new House map comprises 102 Republican-leaning districts and 101 Democratic-leaning ones, according to the analysis. The current map has 118 Republican-leaning districts and 85 Democratic-leaning ones.

In the Senate, there’s less of a shift: There would continue to be about 24 Democratic districts and 26 Republican ones, but a few of the more competitive districts become more strongly partisan.

Republicans currently control both chambers, and data analyses suggest the new maps could make legislative elections more competitive — perhaps giving Democrats a better shot at gaining power in this year’s midterm elections, when voters will also pick a new governor. Democrats have long argued that the current maps are partisan gerrymanders designed to benefit the GOP, while Republicans say their long-held majorities reflect the state’s natural political geography and their party’s strong candidates.

“Your state elected leaders determine how much money your school district will receive, what infrastructure projects to be funded, rules for casting your ballots, laws that control professional licenses, as well as important environmental policy for our Commonwealth,” Senate Minority Leader Jay Costa (D., Allegheny) said Friday. “These issues matter to every voter. If a gerrymandered district prevents you from representation that reflects your views, we have a problem.”

The final maps approved Friday were based on preliminary ones approved in December, with a number of changes made based on public comment and feedback from lawmakers.

» READ MORE: Mark Nordenberg on drawing new Pa. legislative maps, GOP attacks, and what comes next

Mark Nordenberg, the former University of Pittsburgh chancellor who chaired the Legislative Reapportionment Commission, said the new changes were made to better reflect local communities, reduce the number of towns divided into multiple districts, and increase the voting power of people of color.

In the Senate map, for example, Nordenberg said “the most dramatic change … is the creation of a new Hispanic influence district in Philadelphia.” It will have a voting-age population that is about 37% Latino and 24% Black.

The commission, which is made up of Nordenberg and the Democratic and Republican leaders of the House and Senate, voted 4-1 to approve the maps. House Majority Leader Kerry Benninghoff (R., Centre) was the sole opposing vote.

There was little dispute over the Senate map.

Not so with the House map.

When the preliminary new House map was unveiled in December, the Republicans on the panel voted against it, with Benninghoff immediately calling it a Democratic gerrymander and leading a campaign to attack the proposed map and the way it was drawn.

» READ MORE: We went deep on the initial version of the new state House map

That continued Friday, when Benninghoff unveiled an alternative proposal that he said would create more majority-minority districts and split fewer municipalities. He also lashed out at Nordenberg, saying the chairman “apparently abdicated” his role as a nonpartisan tiebreaker: “Rather than being an umpire, he has instead chosen to pick up a bat and a glove so he can play on a team that best fits his own political interests.”

“If you believe in population equality, you will vote for my amendment,” Benninghoff said during the commission hearing. “If you believe in keeping municipalities whole, you will vote for this amendment. If you believe that partisan gerrymandering is wrong, you will vote for this amendment. And finally, if you truly believe in providing equal opportunity for Pennsylvania’s growing Hispanic and Black populations to participate in our democratic process and to actually elect members to the House, you must vote in favor of this amendment.”

The amendment was voted down, 3-2.

House Minority Leader Joanna McClinton (D., Philadelphia), the first Black woman to hold the leadership position in the legislature, said she was offended by Benninghoff’s remarks.

“I’m a few greats but not too far removed from enslaved Africans in this country who had no right to vote whatsoever,” she said, “so to suggest … I’m trying to disenfranchise people of color, whether they’re African American, Latino, or any other color — to me, to my caucus, it is very personally disrespectful.

“I hope that my counterpart is just misinformed,” McClinton added, “and is in fact not trying to mislead people over something that is so serious, about fairness and equality. ... The simple truth is that the House map fairly reflects the significant demographic changes since the last census.”

» READ MORE: We went deep on the initial version of the new state Senate map

Redistricting is inherently political, and the commission had to consider multiple rules and principles. Those included the state constitution’s requirements that districts be as compact as possible and split as few counties and towns as possible, as well as federal voting rights law regarding the representation of voters of color.

Principles and interests can sometimes be in tension, and every decision ripples out across the map. For example, communities of color don’t only live in neatly compact areas within strict municipal boundaries, so drawing voters of color together can mean having to cut across town lines or draw a sprawling district border.

And of course, partisan interests are front of mind, especially since four of the five commission members are elected legislative leaders with vested interests in protecting and growing their caucuses.

Consider that the major population changes from the 2010 to 2020 Census include growth in urban and suburban areas, decline or lagging growth in rural and exurban areas, and growing numbers of residents of color. Those shifts are broadly beneficial to Democrats, meaning maps that reflect those changes can end up benefiting Democrats without partisan intent.

And because the maps used over the last decade had a built-in Republican advantage, efforts to draw districts that are more responsive to changes in voting patterns across elections will mean eroding some of that Republican tilt.

» READ MORE: 5 takeaways from Pennsylvania’s initial state House and Senate map proposals

Across a number of quantitative tests for spotting gerrymanders, the new districts maintain a slight Republican skew, but are close to evenly split. That’s likely an intentional decision of the mapmakers, because the “political geography” — with Democrats heavily clustered in urban and dense suburban areas, and Republicans more scattered across the rest of the state — gives Republicans a structural advantage.

The analysis conducted by the Princeton Gerrymandering Project, which uses the average two-party vote share from the 2016 and 2020 presidential elections and then takes into account the 2016 and 2018 U.S. Senate races, shows the degree of the partisan change in the maps.

The new Senate map has 15 strongly Democratic seats, one more than in the current map, and 21 strongly Republican seats, up from 19. Of the more competitive seats, there would be nine that lean Democratic, instead of the current 10, and five that lean Republican, instead of the current seven.

There are significant shifts in the House map, which has been more skewed toward Republicans over the last decade.

The new House districts will have 75 strongly Democratic seats, up from 68 in the current map, and 26 districts that lean Democratic, up from 17. The number of strongly Republican districts increases from 83 to 86, while the number of Republican-leaning districts falls from 35 to 16.

That means the House map goes from a 118-85 split in favor of Republicans, to a 102-101 split that barely favors the GOP.

» READ MORE: Pennsylvania Republicans want a lot more power in redistricting for state maps

Elections are won by individual candidates on ballots cast by individual voters, and past elections don’t always neatly predict future ones. There are Democrats who win in Republican districts, and vice versa.

Republicans still hold an edge in both maps, and incumbency can be a powerful advantage. The analysis helps show the underlying partisanship in each district, but it’s not an explicit prediction. How red or blue the district is sets the playing field, but candidates, campaigns, the broader national and local political environment, and other factors also matter.

More important than using the numbers to predict who wins is to consider how different maps compare using the same metrics.

And on that front, it’s clear that the new maps favor Republicans a lot less than the old ones do.