Following Tuesday's showdown between President Donald Trump and Democratic nominee Joe Biden means more than identifying the battleground states and remembering how the Electoral College works.
With a massive turnout expected, an avalanche of mail-in ballots to process, differing state policies on counting them and an army of election lawyers ready to pounce, election night has the potential to end in anything from an early landslide to a drawn-out brawl that carries into 2021.
What follows is an hour-by-hour guide for what to look for as American voters choose a president, decide who controls the Senate, pick their House representatives and weigh in on local races and ballot issues. Times are Eastern Standard; for states with multiple closing times, the latest one is shown. South African time is shown in brackets.
7 pm (2 am)
POLLS CLOSE IN: Georgia, Indiana, Kentucky, South Carolina, Virginia, Vermont
WORTH WATCHING: Based on number-crunching by their decision desks, television networks and the Associated Press start making their unofficial but much-watched declarations of who won where, and how many electoral votes Trump and Biden have locked up. The winner is the one who reaches 270. An early measure of Trump's vulnerability is whether Georgia is competitive. The state has gone Democratic in just three presidential elections since 1960 -- and two of those were when native-son peanut farmer and former Governor Jimmy Carter led the ballot.
GOOD FOR TRUMP: If Virginia takes a while to be called. In 2016, an early hint that Trump was doing well was that Virginia, a once-Republican stronghold that had recently gone to the Democrats, was too close to be called for Hillary Clinton for hours after polls closed.
GOOD FOR BIDEN: A win in Georgia would be an early hint at a very strong night.
SENATE STATUS: Democrats would be downright giddy if they could oust Kentucky's Mitch McConnell, the Senate majority leader since 2015, or South Carolina's Lindsey Graham, a onetime Trump critic who has become one of his most stalwart defenders. Neither outcome is likely, but not out of the question. A better chance for an early Democratic Senate pickup is in Georgia, where, unusually, both incumbent Republican senators are on the ballot, and, also unusually, a runoff election (or two) would be held in January if no candidate wins an outright majority.
ALSO WATCH FOR:
* Georgia is set to elect a congressional candidate who has embraced the QAnon conspiracy theory, which asserts in part that Democrats are running paedophilia rings. Republican Marjorie Taylor Greene is running unopposed to fill a vacant seat in the state's 14th congressional district.
7:30 pm (2.30 am)
POLLS CLOSE IN: North Carolina, Ohio, West Virginia
WORTH WATCHING: Counting of mail-in ballots began two weeks ago in North Carolina, so results from there may come swiftly. Appalachia was Trump country in 2016. It's home to many of the non-college-educated White voters who form Trump's base as well as the coal industry he's tried to revive, to limited effect.
GOOD FOR TRUMP: He needs to keep all three of these states in his column, and only West Virginia is assured.
GOOD FOR BIDEN: A win in North Carolina or Ohio. North Carolina has voted for the Democratic presidential candidate only once in the past 10 elections when it went for Barack Obama in 2008, but changing demographics have turned it into a toss-up.
SENATE STATUS: North Carolina Republican Senator Thom Tillis tested positive for Covid-19 after attending the mostly mask-free White House introduction of Supreme Court nominee Amy Coney Barrett on Sept. 26. Then his Democratic challenger, Cal Cunningham, acknowledged an extramarital affair that had left a trail of flirtatious text messages.
ALSO WATCH FOR:
* No Republican has won the presidency without Ohio. Trump probably can't, either. The state went so big for him in 2016 that its battleground status seemed in jeopardy, but Democrats did well in the 2018 midterm congressional elections. Biden is counting on support in and around the "three C" cities of Columbus, Cincinnati and Cleveland.
8 pm (3 am)
POLLS CLOSE IN: Alabama, Connecticut, Delaware, Florida, Illinois, Maine, Massachusetts, Maryland, Mississippi, Missouri, New Hampshire, New Jersey, Oklahoma, Pennsylvania, Rhode Island, Tennessee, District of Columbia
WORTH WATCHING: Pennsylvania may be key not just to who wins, but when a winner is known.
GOOD FOR TRUMP: Trump is now a Floridian, having changed his official residence, and carrying the state as he did in 2016 is a must. A brightening economic picture there could help.
GOOD FOR BIDEN: "We win Florida, and it's all over," Biden has said, and that's probably true. In 2016, people 65 and older accounted for 30% of Florida's vote and supported Trump by a 17-point margin. Biden has made inroads by telling seniors that Trump's coronavirus response left them vulnerable.
TIMING ALERT: Florida has experience with handling large numbers of absentee ballots, and this year it permitted counting of mail-in ballots to begin 22 days early. That means it may give a result rapidly. But the opposite is possible in Pennsylvania, where ballot counting is not permitted to begin until 7 a.m. on Election Day and election laws allow for ballot challenges and appeals to drag on.
SENATE STATUS: Alabama's Doug Jones, a Democrat in a very conservative state, represents the Republicans' best chance to flip a seat. The Republican candidate is former Auburn University football coach Tommy Tuberville. Maine Senator Susan Collins, in office since 1997, has found her brand of centrist Republicanism to be a tough fit in the Trump era. Her Democratic challenger, Maine House Speaker Sara Gideon, says Collins "made the choice not to stand up to this president."
ALSO WATCH FOR:
* At this point in the night, the electoral maps on television news networks may look good for the Republicans, but remember there is often a "blue shift" when mail-in votes and provisional ballots that have been held for days to confirm a voter's eligibility are added in the following days or weeks and the totals move toward the Democrats.
* Illinois Governor J.B. Pritzker, a Democrat, wants voters to approve replacing the state's 4.95% flat tax on income with a graduated tax starting at 4.75% and reaching 7.99% for single filers earning more than $750,000 and joint filers with income of more than $1 million. Illinois has a $4.1 billion budget deficit, and its credit rating is a step above junk.
* Mississippi votes on a new state flag to replace one that included the Confederate battle emblem. The one up for approval features the phrase "In God We Trust" under a magnolia, the state flower.
* New Jersey Representative Jeff Van Drew, who was elected in 2018 as a Democrat, is now a Republican who pledged his "undying support" for Trump after breaking with his party on impeachment. The Democrat trying to deprive Van Drew of a second term is Amy Kennedy, whose husband, Patrick J. Kennedy, is a former congressman.
8:30 pm (3.30 am)
POLLS CLOSE IN: Arkansas
WORTH WATCHING: Since favorite son former President Bill Clinton is not running again, this is a Republican lock. Go get a snack.
9 pm (4 am)
POLLS CLOSE IN: Arizona, Colorado, Kansas, Louisiana, Michigan, Minnesota, Nebraska, New Mexico, New York, North Dakota, South Dakota, Texas, Wisconsin, Wyoming
WORTH WATCHING: If Trump can retain all the states he won by at least 1 percentage point in 2016 -- giving him 260 electoral votes, 10 shy of victory -- he'd need to win just one of Pennsylvania/Michigan/Wisconsin.
GOOD FOR TRUMP: Keeping Michigan in his column is among his hardest and most important tasks. He won there by 0.21% in 2016, or fewer than 11,000 votes, which was the narrowest margin of that election. Flipping Minnesota, a Rust Belt-adjacent state where he lost by less than 2 percentage points in 2016, would give him extra wriggle room. That's a tall order, since Minnesota has gone for the Democrat in every presidential election since 1976.
GOOD FOR BIDEN: Arizona, Michigan, Wisconsin are three electoral bounties Biden could steal from Trump's column. Even more ambitious would be a win in Texas, which would signal a Biden landslide and leave Trump with little room to contest the election results. Record voter participation in Texas makes the outcome that much harder to predict.
TIMING ALERT: In Pennsylvania and Wisconsin, the processing and counting of mail-in ballots can't begin until Election Day, and Michigan can't start processing them -- like opening envelopes and preparing ballots for scanning -- until Nov. 2. So the states could need overtime to declare a winner.
SENATE STATUS: If retired astronaut Mark Kelly unseats Republican Senator Martha McSally, Arizona would have two Democratic US senators for the first time since the 1950s. Republican Senator Cory Gardner of Colorado, seeking a second term, is another target of Democrats, whose candidate is John Hickenlooper, a former governor and unsuccessful 2020 presidential candidate. In 2016, Gardner said he wouldn't be voting for Trump because he "cannot and will not support someone who brags about degrading and assaulting women." Since then, Gardner and Trump have had a rapprochement.
ALSO WATCH FOR:
* One wrinkle in Minnesota is musician Kanye West, whose fitful attempt at a presidential campaign largely fizzled but who succeeded in getting his name on the ballot there and in 11 other states.
* Can Democrats win statewide in Texas? With a growing population that's young and diverse, not to mention 38 electors for the winner, Texas presented an intriguing target for the Biden campaign, which had to weigh how much money to spend there. Texas hasn't voted for a Democratic presidential candidate since Carter in 1976.
* Trump lost New York, his home for 73 of his 74 years, by more than 22 percentage points in 2016. In the modern two-party era, only Mitt Romney's 2012 loss in Massachusetts (23 points) was a worse home-state drubbing.
* If approved by voters, Colorado's Proposition 115 would prohibit abortions after 22 weeks of pregnancy, unless the woman's life is in jeopardy. And Louisiana Amendment 1 would declare that the state constitution doesn't protect the right to have an abortion -- which would matter should Roe vs. Wade, the federal ruling legalizing abortion, be struck down by the Supreme Court.
* Arizona Democrats believe they can end one-party domination of the state legislature after decades of Republican control.
10 pm (5 am)
POLLS CLOSE IN: Iowa, Montana, Nevada, Utah
WORTH WATCHING: Trump is sending record subsidies to farmers, a key segment of his rural base in the Midwest and South. Trump won Iowa by 9.4 percentage points in 2016 but his polling lead over Biden has been much narrower.
Iowa, the nation's largest producer of hogs and second-largest producer of soybeans, has been hit by Trump's trade war with China.
GOOD FOR TRUMP: Holding Iowa, winning Nevada.
GOOD FOR BIDEN: Winning Iowa and especially holding Nevada, where record unemployment from the crash of the hospitality/gambling industry threatened the traditionally formidable, get-out-the-vote operations led by Democratic labor groups.
SENATE STATUS: Senator Joni Ernst of Iowa is a first-termer who is part of the Senate Republican leadership team and was the only incumbent Republican senator up for re-election to speak at the party's convention in August. She is one of the top targets of Democrats. Another is first-term Senator Steve Daines in Montana. His Democratic challenger is outgoing Governor Steve Bullock, who -- like Hickenlooper in Colorado -- started running for Senate only after failing to become the party's nominee to challenge Trump.
ALSO WATCH FOR:
* The nation's most competitive governor's race is the one to succeed the term-limited Bullock in Montana. Republican U.S. Representative Greg Gianforte, who was sentenced to 40 hours of community service and 20 hours of anger management classes for assaulting a reporter in 2017, faces Mike Cooney, who has served as Bullock's lieutenant governor.
11 pm (6 am)
POLLS CLOSE IN: California, Idaho, Oregon, Washington
WORTH WATCHING:
With only Alaskans and Hawaiians still voting, this is when the TV networks and the AP could call the presidential race if the result has become clear. Obama was declared victorious at 11 p.m. sharp in 2008, as the reliably blue West Coast put him over the 270 mark. This year, the experts who run the numbers and make these calls have the additional challenge of factoring in how many mailed ballots might be contested or are yet to be counted.
ALSO WATCH FOR:
* In California, Proposition 16 asks voters to end their state's prohibition on affirmative action by reversing a 24-year-old ban on giving racial- and gender-based advantages in hiring, for contracts, and in college enrollment. Arizona, Florida, Idaho, Michigan, Nebraska, New Hampshire, Oklahoma and Washington also restrict using gender and race criteria.
1 am on November 4 (8 am)
Voting ends as polls close in Adak, Alaska, and it will all be over but the counting.
November 4 and beyond
Even in normal years, the counting of ballots -- particularly absentee and provisional -- continues for days, even weeks, after an election. Sometimes, as in 2000, a presidential race is close enough for those revised counts to matter. Rules vary by state about what outcome triggers challenges and recounts.