State ballot measures explained: The crucial local votes on abortion, wealth taxes, and election rules

Voters in more than three dozen states will decide around 150 ballot measures on November 3, alongside the congressional contest that has dominated coverage of November's U.S. midterm elections.

The measures on the ballot span abortion access, the rights of transgender athletes and what would be the world's first billionaire tax.

Arizona, Colorado, Nebraska and Washington will decide whether to bar transgender girls and women from playing for all-female sports teams.

Republican candidates have sought to highlight the issue on the campaign trail.

That follows political strategists crediting President Donald Trump's attacks on transgender rights in 2024 with helping him to victory.

Proponents of the limits say they protect girls and women.

Critics say they discriminate against transgender students.

Arizona and Nebraska have already passed laws that prohibit transgender girls and women from teams that align with their gender identity.

Arizona's referendum would expand its law to apply to private schools.

It would also require all schools to ensure bathrooms and locker rooms are open only to athletes whose birth certificate matches the gender associated with the facility.

Nebraska's measure would codify the ban in the state constitution, making it harder for lawmakers to reverse.

Washington's law would require any athlete seeking to join a girls' team to have their "biological sex" verified by a healthcare provider.

Some opponents have said that provision could result in unnecessary and invasive examinations.

Two states will also vote on restricting gender-affirming care for minors.

A ballot measure in Colorado would ban transition-related surgeries for minors.

Missouri already has a law prohibiting gender-affirming medical treatment for children.

Voters there will decide whether to add that ban to the state constitution.

Abortion is also on the ballot in Idaho, where voters will decide whether to establish the right to abortion up to fetal viability, generally considered to be around 24 weeks of pregnancy.

The state has banned virtually all abortions since 2022, when the U.S. Supreme Court eliminated a nationwide right.

Missouri voters face a ballot measure that would reverse their decision two years ago to overturn the state's abortion ban, and again prohibit most abortions.

The 2024 referendum was citizen-initiated.

This year's ballot measure was brought forward by the Republican-controlled legislature.

The measure also bans gender-affirming care for minors.

California, Colorado and Nevada will decide whether to require voters to provide the last four digits of a government identification card, such as a Social Security number or a driver's license, when voting by mail.

Arizona has a referendum that would require photo ID for mail-in ballots.

The measure's language does not specify how that would work.

Starting in 2025, Trump led a Republican push to redraw congressional maps in several states, aiming to turn Democratic-held seats into GOP-leaning districts.

The resulting fight between both parties appears likely to extend to 2028.

Two notable ballot measures will shape the battlefield.

Missouri residents will vote on a Republican-drawn map that would break up the state's only Democratic-leaning seat, after courts ruled it can only take effect with voter approval.

In Maryland, voters will decide whether to amend the state constitution to make it easier for lawmakers to draw new congressional districts.

That would open the door for the Democratic-controlled legislature to eliminate the state's only Republican-leaning seat in 2028.

A California ballot measure, Proposition 40, would create the world's first billionaire tax.

It would impose a one-time 5% wealth tax on the worldwide assets of each of the state's roughly 250 billionaires.

Most of the revenues would be earmarked for healthcare programs.

Taxing the ultrawealthy is broadly popular, especially among Democrats.

But the referendum has divided California Democrats.

Governor Gavin Newsom, a potential 2028 presidential candidate, opposes the measure, warning it could drive successful tech companies to other states.

In Montana, voters will decide whether to bar corporations from spending money on elections.

That is a novel legal strategy to sidestep the U.S. Supreme Court's landmark Citizens United ruling in 2010.

That decision found corporations and unions have a constitutional right to spend unlimited funds on campaigns independently from candidates, opening the door to super PACs and "dark money" groups that do not disclose their donors.

Alaskans will decide whether to retain the state's unusual "ranked-choice" election system, which asks voters to rank each candidate in order of preference.

If no candidate reaches 50%, the candidate with the lowest total is dropped, and their supporters' votes are reallocated to the next choice on the list, until a winner emerges.