Your hour-by-hour form guide to the US midterm elections

In a matter of hours, we'll start to learn whether Donald Trump's Republican Party has retained control of the US Congress, or if Democrats are flipping the House of Representatives, the Senate, or both.All 435 seats in the House are up for election, and Democrats would need a net gain of three, compared to the 2024 election result, to take control there.Roughly a third of Senate seats are up for grabs, and Democrats would flip that chamber if they can get to 51 seats (a gain of four).So when will we know a result? As always, it depends on how close things are.In 2022, it took days to confirm control of the House and Senate. In 2020, it took weeks to know who would control the Senate because of a runoff election in Georgia. This year, polls are pointing toward a rosier picture for Democrats. If they're correct, things might be clearer faster.We'll have results across the day on ABC News. Here are a few things to keep in mind when they arrive.What to watch, hour by hourUS election nights can be slightly overwhelming, with hundreds of races, thousands of counties, and election results touchscreens as far as the eye can see (I'll be at one all day on ABC News Channel).Here's a quick guide on the most important things to keep an eye on, and when is a good time to take a break and touch some grass (all times below are in Australian Eastern Daylight Time).The first polls close at 10am in most of Indiana and Kentucky, and the final polls close in Alaska's Aleutian Islands at 5pm.10amWe're starting slow, with polls closing in just two states this hour (and not even the whole states). Check in on Kentucky's 6th district, because if the Democrats gain this seat it could be an early sign the Republicans are going to have a tough day.11amSix more states start to report figures, including Georgia, where incumbent Democrat Jon Ossoff is the firm favourite.There's a Republican-held Senate spot in South Carolina that's attracted a bit of chatter in the final weeks of the campaign. This seat was held by the late Lindsey Graham, and now his sister Darline is the candidate. South Carolina is a very red state, but this year's race could be more competitive than usual.South Carolina senator Lindsey Graham died in July. (Reuters: Kenny Holston/The New York Times/Pool)We should also see a lot of votes in Florida this hour, where there are many competitive House races.If you're happy with an early lunch, now would be one of the best times of the day to pause for elevenses, because things are about to speed up dramatically. But be quick!11:30amThis is where counting starts in two key Senate races: Ohio, which appears to be very competitive, and North Carolina, which Democrats appear well-placed to flip. If Republicans appear competitive in this state it could be a long count.12pmThis is 8pm on the east coast of the USA, and we'll start to see figures from a further 18 states, including in the key Senate races of Michigan, Maine, Kansas, and one of the most discussed races this cycle, Texas.If the polls are accurate, we may also know if Democrats are flipping enough seats to take control of the House of Representatives (although the party can't officially cross the majority line of 218 seats until polls close on the west coast).1pmIn this hour we'll start to see returns in Iowa and Nebraska, where Dan Osborn — the main challenger to the Republican incumbent — is a mechanic running as an independent.2pmFive more states close this hour, including the Senate races in Idaho and Montana, both of which are expected to go the Republicans' way. By now, counting will be underway in the vast majority of competitive races. If you didn't take up the chance for an early lunch, or fancy another snack, this might be a good time.3pmCalifornia, the most populous state in the union, ends voting here, and counting begins in its 52 congressional districts. Democrats hold 43 of them, so if they are on track to control the House they will need to wait for races to be called here before officially crossing the majority line of 218.4pmPencils down in Hawaii and Alaska, which will attract more attention than usual this year, with its Senate race of particular interest.Democrat Mary Peltola is hoping to defeat Republican incumbent Dan Sullivan, who is up against an independent candidate also called Dan Sullivan. In Alaska, Republican senator Dan Sullivan has had to contend with a challenger with the same name. (AFP: Getty Images/Andrew Harnik)The second Sullivan is unlikely to poll very well, but Republicans are concerned that in a competitive race it could confuse enough people to make a difference. The Trump administration has directed the Department of Justice to block certification of the Senate race if Sullivan loses because of votes for the other Sullivan.5pmEveryone else in Alaska and the USA finished voting an hour ago, except for a single precinct in the Aleutian Islands. Fewer than 10,000 people live across the 11 towns and villages in the islands, and in the 2024 election just 154 voters were registered in this final precinct, of which 19 cast a vote.Typically, Alaskan electoral authorities wait until all polls are closed in the state. In 2024, we got our first votes in Alaska at 5:07pm AEDT.If Alaska's Senate race is close, it could be a long time before we know the winner. The state uses an Australian-style ranked choice voting system (we call this preferential voting), but preferences are unlikely to be counted for days or even weeks.Figures can shift during the countAll day the ABC will be reporting live results and calls from news agency Associated Press, which has thousands of staff around the country tabulating figures and calling races.We need to rely on an agency like AP because the US doesn't have a national body running its elections, as the Australian Electoral Commission does here. Elections are administered and held under rules set at the county and state level.That means the results can be reported in wildly different ways and need to be interpreted very carefully.Some states like Florida — which has already started scanning postal votes — will report early votes quickly.Other states report election day votes first, followed by the postal votes.Postal voters tend to be more likely to vote Democrat than Republican, which means the totals can shift as different kinds of votes are added. In Florida, it wouldn't be a surprise to see Republicans improve as the count goes on, but in Wisconsin and Pennsylvania the shift could be in the other direction.Some have tried to argue that these shifts throughout the count are evidence of vote tampering or corruption, but in reality, it is just a result of the order that votes are counted in each state.There are also some states that just take a very long time. For example, most people vote by mail in California, which has become notorious for taking a long time to count.Redistricting has moved the starting lineIn much of the United States, state politicians control the drawing of electoral boundaries, and since the last election, we've seen an extraordinary amount of redistricting occurring outside the usual 10-year cycle.It started last year in Texas when, encouraged by Donald Trump, Republicans moved to redistrict the state's congressional boundaries to notionally give themselves another five or so seats.In response, voters in California approved new Democrat-drawn maps that gave the party around five or so additional seats.Redistricting has occurred in seven other states since then, mainly improving the map for Republicans. That means that, even if they're having a terrible night nationally, Republicans are expected to gain some seats in the House of Representatives.Democrats need to gain three seats compared to their 2024 result to flip control in the House, but because of this redistricting their magic number is actually a bit higher than that.