Republicans just passed legislation that would overhaul Pennsylvania’s elections.

The Democratic governor is set to veto it.

And then we’ll move on to the next chapter of the escalating voting wars that have engulfed politics in Harrisburg and across the country, with at least one thing clear: As Democrats and Republicans fight over how ballots are cast and counted, few acknowledge just how complicated running elections is, and how unpredictable the impact of major changes can be.

Republicans in the state Senate gave final approval Friday afternoon to a House-passed bill that would implement stricter voter identification requirements, in-person early voting starting in 2025, signature verification for mail ballots, and other major changes.

Republicans call it a sweeping modernization of an outdated Election Code that would make elections more secure and accessible — making it “easier to vote and harder to cheat,” as State Rep. Seth Grove (R., York), the bill’s author, often says. “The most comprehensive election security and accountability measure” being considered in the country, State Rep. Martina White (R., Philadelphia) said.

Democrats decry it as voter suppression rooted in lies about the 2020 presidential election, noting that Grove led a group of GOP lawmakers who called on Congress to reject Pennsylvania’s results. “This is Jim Crow 2.0,” said state Sen. Sharif Street (D., Philadelphia). State Rep. Malcolm Kenyatta (D., Philadelphia) called it “nothing more than voter suppression in bad drag.”

The reality is more complex.

» READ MORE: Pa. Republicans propose major election overhaul, with stricter voter ID rules and in-person early voting

Even though voter fraud is exceptionally rare, much of the legislation focuses on tightening election security and could raise some barriers to voting — including through its voter ID rules, restrictions on mail ballot return options, and signature verification requirements.

But it’s also not simply a partisan grenade: The ID requirements are weaker than what other states have enacted, it would codify things like mail ballot drop boxes into law, and create more explicit rules for “curing” ballots on which voters made minor mistakes.

Even some opponents credit Republicans for political savvy in crafting a bill that’s less easily dismissed as voter suppression than measures in other states.

“It’s complex, but it’s a smart, strategic bill,” said Khalif Ali, the head of Common Cause Pennsylvania, a good-government advocacy group opposed to the legislation. “It’s definitely the wolf in sheep’s clothing. There are some decent pieces in there that we can’t say honestly … that we would be against.”

Ali spoke approvingly of increased poll worker pay and changes that would allow processing of mail ballots before Election Day — something elections officials have long requested and that could have prevented the days-long wait for results last fall. But he also decried signature verification for mail ballots and other provisions as making it harder for some people to vote.

“Item by item, there really are good things in the bill,” said Al Schmidt, the lone Republican on Philadelphia’s elections board, who became a target of threats and harassment for pushing back against lies and conspiracy theories about the 2020 election. “And then there are other things in the bill that are clearly intended to indulge in … this fantasy of widespread voter fraud.”

» READ MORE: Fact-checking false claims about Pennsylvania’s presidential election by Trump and his allies

Some of the bill’s proposals may affect different voters in different ways.

For example, cutting off mail ballot applications earlier — 15 days before Election Day instead of seven — could mean some voters who would have requested ballots in those last two weeks now won’t be able to vote by mail. But the current seven-day window is so tight it doesn’t match Postal Service standards and already disenfranchises thousands of voters.

Making matters more complicated, the bill would make many changes at once. But voter behavior is complex, election law is nuanced, election administration is challenging, and the real-world effects of changes can defy expectations.

“It’s the question of unintended consequences, in part, and the interactions between these different kinds of provisions,” said Dan Hopkins, a political scientist at the University of Pennsylvania. “…These policies can be hard to evaluate, because people may react to them in unexpected ways.”

Take voter identification requirements, which a decade ago helped spark an earlier round of voting wars. That included Pennsylvania enacting one of the nation’s strictest mandates in 2012 — a law courts struck down as unconstitutional before it took effect.

Voter ID has long been a political flashpoint, but its impact can be easily misunderstood, partly because it doesn’t take place in a vacuum. A strict requirement can make it harder for some already marginalized groups, including poor and low-income voters, to cast ballots. But it can also spark backlash and mobilization efforts, boosting turnout. Just think about all the time — and money — spent last year on voter education campaigns to prevent “naked ballots” and ensure mail ballots were returned on time.

» READ MORE: It didn’t need to take that long: What Pennsylvania’s election could have looked like with earlier counting

Or consider in-person early voting, which the Republican proposal would allow for a six-day period beginning in 2025, after the next presidential race. That may seem like a major expansion of voting access. But it may do little to expand the electorate — especially when mail voting is widely available, like in Pennsylvania — instead mostly making it more convenient for people who would have voted anyway.

Then there’s the challenge of actually implementing election law in 67 different counties run by 67 different elections offices.

Sparse funding, staffing, and other logistical constraints affect how policies are carried out. That’s already the case with drop boxes and satellite elections offices, which some counties began using last year to help voters request and return mail ballots. Scarcer resources mean some counties scaled back those options this year, including Philadelphia, which went from having 17 such locations to just one.

Republicans railed against and sued over drop boxes last year, since they aren’t explicitly mentioned in current law, but courts upheld their use. While some prefer to ban them, the bill would explicitly allow for ballot return locations — while also adding new restrictions. It would require them to be staffed by poll workers from both parties, video recorded, and open only from 7 a.m. to 8 p.m. the week before Election Day, instead of 24/7 for weeks, as some counties have done.

Setting up drop boxes under such rules may not be worth it for some counties.

And while Republicans tout the inclusion of drop boxes and say the requirements would make their use more uniform, it would likely result in some patchwork of implementation. Counties wouldn’t actually be required to have drop boxes at all. It would also limit the large, densely populated and more Democratic counties that would benefit most from their use. Counties wouldn’t be allowed more than one box per 100,000 residents and would be limited to 10 total, no matter their population.

Philadelphia, which has 1.5 million residents, had 14 drop boxes for this year’s primary.

“It’s the arbitrary limits I don’t understand,” Schmidt said, “particularly since they affect Philadelphia and it’s in a disproportionate and negative way.”

» READ MORE: Philly elections officials reverse course and reject undated mail ballots amid impeachment threat

There also could be small, overlooked details that end up having big implications.

Inner secrecy envelopes, for example, had long been required for absentee ballots, to give voters anonymity after their ballots were removed from mailing envelopes. Some counties would nevertheless count “naked ballots” missing those secrecy envelopes, erring on the side of counting votes. But when the state Supreme Court ruled last year that naked ballots had to be rejected, the seemingly small detail became a major disenfranchisement concern.

Other provisions can seem big but end up having little apparent impact. The 2019 bipartisan election overhaul that expanded mail voting also removed straight-ticket voting, the option for voters to pick candidates from the same party for every race on the ballot at once. Democrats decried it as suppressive, some voted against the bill because of it, and at one point Wolf vetoed it. But the issue has quietly disappeared from the discussion.

So, it’s complicated.

After Wolf vetoes the bill, the fight will almost certainly move from the Capitol building in Harrisburg to the campaign trail across the state, especially in the 2022 governor’s race.

Both sides will say they need to win the governor’s mansion to protect elections and defend democracy.

And the voting wars will continue.