Hundreds of lawsuits about voting have been filed before the Nov. 3 election. The cases concern the fundamentals of the American democratic process, including how ballots are cast and counted. A look at some of the top lawsuits in battleground states:

ARIZONA: A federal judge ruled in favor of Democrats by holding that voters who neglected to sign their early ballots before mailing them in get up to five days after the election to fix the problem. The judge ruled that it was not fair for elections officials not to give voters a chance to "cure" the problem. The case has since been appealed to the 9th U.S. Circuit Court of Appeals.

IOWA: Several of the election disputes involve mail-in voting rules. In one, Democrats are challenging a new GOP-backed law that blocks county auditors from filling in any missing voter ID information on absentee ballot applications returned by voters. In a related case, Republicans have persuaded judges to invalidate tens of thousands of absentee ballot applications submitted by voters whose ID information had been pre-filled on the forms by county auditors. Democrats are challenging the Republican secretary of state's rules that drop boxes must be located on county property and not at grocery stores or other community sites.

MICHIGAN: Officials are mired in litigation over how long ballots can be counted after Nov. 3. State law requires the ballots to be counted by Election Day. But a state judge, citing mail delays, has ordered that they be counted if they are postmarked by Nov. 2 and arrive by Nov. 17. The Republican-led Legislature is appealing. The issue could be crucial in determining the winner of the presidential contest in the state, which Trump won by less than 10,000 votes in 2016. Absentee voting has only been permitted since 2018, but some 2.7 million people have requested absentee ballots.

MINNESOTA: Republicans have challenged the state's Nov. 10 deadline for mail-in ballots to arrive this year, a 7-day extension granted because of the pandemic. Under a consent decree, the ballots must be postmarked by Nov. 3. Republicans are appealing the plan. Meanwhile, Democratic U.S. Rep. Angie Craig has challenged a state law that pushed voting for her 2nd District seat to February due to the Sept. 21 death of Legal Marijuana Now Party candidate Adam Weeks. A delay could have national implications if the presidential election remains in dispute in January and the seat remains empty when her first term concludes in January.

NEVADA: The Democratic-led Legislature passed a law this year that sends mail-in ballots to every registered voter and lets someone else return it on the voter's behalf. The latter practice, known as ballot harvesting, had previously been illegal. The law, signed by Democratic Gov. Steve Sisolak, also let county election officials start counting mailed ballots on Oct. 19. The Trump campaign challenged the law, suggesting mail-in voting was rife with fraud, but a federal judge said they failed to show any actual harm.

NEW HAMPSHIRE: A judge in April struck down a 2017 New Hampshire law that made it more difficult for people to vote if they registered the month before the election. The judge said the added paperwork was "unreasonable." The Republican-led Legislature had passed the law after Trump's loss there in 2016. State officials have appealed to the state Supreme Court. Meanwhile, the American Federation of Teachers, citing the pandemic, challenged some state voting procedures in August, including an Election Day deadline and lack of prepaid postage for absentee ballots. Both the Trump campaign and state officials pushed back, and a judge mostly dismissed the suit while ordering the state to help would-be voters obtain registration forms.

NORTH CAROLINA: The Trump campaign and the Republican National Committee are suing in federal court to block state election officials from enforcing rule changes that could boost the number of ballots counted. That includes guidance that will allow the fixing of absentee ballots with deficient information without forcing the voter to fill out a new blank ballot.

OHIO: A federal judge in Cleveland this month ruled that a new Ohio directive allowing ballot drop boxes at locations "outside" boards of elections means they can be placed at multiple locations — a ruling at odds with the intention of the state elections chief. It's not yet clear how many drop boxes will be available across the state before the election. Republican Secretary of State Frank LaRose appealed, and on Friday a three-judge panel on the 6th U.S. Circuit Court of Appeals approved his request to put the lower court's decision on hold. A state appeals court ruled that requests for an absentee ballot cannot be sent by fax or email, finding it could swamp local election officials and threaten the security of the election.

PENNSYLVANIA: Pennsylvania has seen a frenzy of election-related suits as state officials prepare for some 3 million people, about half the expected turnout, to cast mail-in ballots. Trump's campaign has asked the courts to bar counties from using unstaffed drop boxes or mobile sites to collect mail-in ballots; to throw out state guidance on signature discrepancies; to overturn a county residency requirement on poll watchers; and to let campaign representatives watch people register or fill out mail-in ballots in election offices. On Saturday, a federal judge dismissed challenges to the poll-watching law and efforts to limit how mail-in ballots can be collected and which of them can be counted. Republican lawmakers have asked the U.S. Supreme Court to reverse a ruling that gives counties three days after Election Day to receive and count eligible ballots.

VIRGINIA: The key court case over the election in Virginia involves the requirement that absentee voters find a witness to watch them sign their ballots. After the League of Women Voters filed suit over the issue, a federal judge issued a decree allowing voters to skip that step given the pandemic if they don't feel it's safe to have a witness present. The Republican Party of Virginia, which opposed the consent decree, is now challenging the state guidance on the issue, saying it's likely to confuse voters.

WISCONSIN: A federal appeals court upheld a six-day extension for counting absentee ballots in Wisconsin as long as they are postmarked on or before Election Day. The recent ruling gave Democrats in the state at least a temporary victory in a case that could nonetheless by appealed to the U.S. Supreme Court.