Election Day is finally here. Soon enough, returns will start rolling in — and we’ll have a ton of data to sift through. But what should you pay attention to? I’ve broken down the presidential and Senate battlegrounds by when the first polls close at 6 p.m. (Eastern) until the last poll closings at 1 a.m. Only the competitive and major races will be covered here. If you’re interested in when the polls in your state close, check out this map. Even when just looking at this subset of the states, there’s a lot of ground to cover. So let’s get right to it.

6 p.m.

Indiana: The parts of the state in the Eastern time zone (which is most of the state) will close their polls first. (The rest of the state closes its polls at 7 p.m.) The story here is the Senate race and whether Republican Todd Young can complete his comeback against former Sen. Evan Bayh. Results in Indiana have historically come in slowly, so don’t expect a quick result. In 2012, it took until about 9:45 p.m. for the networks to call a race that was decided by nearly 6 percentage points. If there’s a quick call for either Young or Bayh, that could be a sign that his party will have a very good night in the Senate.

7 p.m.

Florida (Eastern time zone only): This is a must-win state for Donald Trump. If Hillary Clinton takes it, Trump will basically have no path to the presidency. (Most experts expect Marco Rubio to hold on to his Senate seat.) Expect a very quick count out of Florida because of the state’s large early vote numbers. You should be careful, though: Don’t read too much into the initial numbers. Democratic areas reported first in the 2014 gubernatorial election, so it’s likely that Clinton will jump out to an early lead. The polls in the western part of the state, which is in the Central time zone, close at 8 p.m. And in both 2012 and 2014, the reported results around that time were close to the final tallies.

Georgia: Trump will probably hold on to beat Clinton here. Still, Georgia — a state with a large black population (32 percent of voters) — could give us a sense of what African-American turnout in the nation will be. The Democratic parts of the state around Atlanta tend to report their votes last, so don’t be surprised if Trump jumps out to a big lead. Watch out for whether the presidential race here is labeled “too close” or “too early” to call. If it’s the former, Trump may be in real trouble in Georgia — and therefore the nation. The latter isn’t bad news for Trump — it just means the networks are waiting on more returns before making a projection.

New Hampshire: Voting ends in most of the state at 7 p.m., although some polling places are open until 8 p.m. The polls have tightened up significantly in both the presidential race in New Hampshire and the state’s Senate race, which is between incumbent Republican Kelly Ayotte and the state’s Democratic governor, Maggie Hassan. Both of those races are too close to call, as is the state’s gubernatorial contest. During the 2014 midterm results, the Republican suburbs around Concord and Manchester were slower to report their results than many Democratic areas were. If that patterns holds, Clinton and Hassan will probably be ahead after results from the first 10 percent of precincts are tabulated. That doesn’t mean they’re going to win.

South Carolina: Trump is widely expected to carry this state –– despite some early polls that suggested the presidential contest in South Carolina could be close. The questions here are similar to those in Georgia. Will the race be called right away? Is black turnout at or above 25 percent in the exit polls, as it was in both 2008 and 2014? If it is, that could be a sign of strong African-American turnout in other states. If it isn’t, that could be bad news for Clinton.

Virginia: Clinton almost certainly must win this state to win the presidency. So it’ll be interesting to see how the race is characterized when the polls close. “Too early to call” is better than “too close to call” for Clinton, although the networks may be cautious about Virginia even though Clinton is favored and go with the latter designation. Clinton’s strongest areas are in the northern part of the state, around Washington, D.C., and they tend to report their votes last. As a result, Trump may lead by a wide margin early. In 2014, Democratic Sen. Mark Warner trailed by 6 percentage points with 34 percent of precincts reporting. He ended up by winning by a point.

7:30 p.m.

North Carolina: The Tar Heel State offers one of the best glimpses of what’s going to happen in the fight over control of the Senate and the presidency. Clinton and Trump have traded the lead in polls of North Carolina. Meanwhile, Republican Sen. Richard Burr has held on to a slim advantage over Democrat Deborah Ross in the projected vote share. A win by the Democrats in either of these races probably signals a very long night for Republicans. As it is in Florida, a lot of the vote in North Carolina is cast early. And those early votes are tabulated quickly, which can be misleading because Democrats do better then. In 2012, for example, President Obama won the early vote but ended up losing the state to Mitt Romney. NBC News’s announcement that Romney had won didn’t occur until after midnight.

Ohio: This is a state that Trump must win. Recent polls have given him a slight edge. The early vote, which will probably come in first, favored Democrats in 2012 and allowed Obama to jump out to a big advantage. That could happen this year too, but as the Election Day votes are counted, Trump should gain ground — possibly even take the lead. That doesn’t mean Clinton is finished in the state, though. To see why, revisit Karl Rove’s infamous Ohio meltdown in 2012 when Fox News called the state for Obama. It did so even when the race was a dead heat and more than 20 percent of the precincts had yet to report. Why? Many of the outstanding votes were from strongly Democratic Cuyahoga County (Cleveland).

8 p.m.

Illinois: Democrat Tammy Duckworth should pick up this Senate seat from incumbent Republican Mark Kirk. Her lead in the polls is so large that the networks will probably call the race in her favor soon after voting ends. If the race is deemed too close to call, it’ll be a long night for Senate Democrats. For Kirk to have any chance, he’ll need to keep Duckworth’s margin in Cook County (Chicago) within 35 percentage points. That seems unlikely.

Maine: The state is one of only two (along with Nebraska) that gives an electoral vote to the winner of each congressional district, in addition to 2 votes for the statewide winner. Trump has led in some of the polls in the state’s 2nd District, which is in the northern part of the state. Historically, if the presidential race in the state is close, the 2nd District gets called after the 1st District and the state overall (which tend to be more Democratic than the 2nd District). This year, the statewide polls have been tight enough that you shouldn’t be surprised if Clinton is awarded only the 1st District’s electoral vote soon after the polls close. If either candidate is declared the winner of all of the state’s electoral votes right away, he or she is going to have a good evening nationally.

Michigan: Almost all the polls close at 8 p.m. in Michigan, but don’t expect a presidential call until at least 9 p.m., when the last precincts shut their doors. Michigan is one of the states that Trump hopes he can pick off from Clinton, but polls show Clinton ahead. Almost all of the vote in Michigan is cast on Election Day. And Clinton needs a strong turnout from heavily African-American Wayne County (Detroit) — Democrats are more reliant on black voters in Michigan than they are in most states outside the South. But don’t be surprised if the Wayne County vote takes a little while to come in. During this year’s infamous Democratic presidential primary in Michigan (which featured a large polling miss and a surprise Bernie Sanders win), Detroit reported its results later than much of the state. That’s why the state wasn’t called for Sanders until late in the vote count –– even though he led for most of the evening.

Missouri: It’s all about the Senate race here. Democrat Jason Kander is looking to complete a shocking comeback against Republican Sen. Roy Blunt. The polls are tight, so don’t expect any resolution for a few hours after voting ends. Blunt is likely to jump out to a lead because vote counting in very Democratic St. Louis has been slow compared with the rest of the state. In the Democratic presidential primary, for example, Sanders held a lead through most of the evening. It was only when the Clinton stronghold of St. Louis came in late in the night that she overtook him.

Pennsylvania: Clinton must win here. The polls suggest that she will. Democrats also probably need to win the Senate race between Democrat Katie McGinty and Republican Sen. Pat Toomey to have a shot at taking control of the Senate. That race is leaning toward McGinty. For either of those Democrats to win, she’ll need a big margin coming out of Philadelphia and its suburbs. Those areas almost always report first, so if you look up and see Clinton and McGinty with big leads in the first returns, that doesn’t necessarily mean they’re going to win the state. Clinton probably won’t be called the winner when the polls close. If, however, the race is said to be “too early” instead of “too close” to call, that could be a sign of a strong Clinton night in Pennsylvania — and nationally.

9 p.m.

Arizona: The surprisingly competitive Arizona presidential race is Clinton’s best chance to pick up a state that Obama didn’t win in either 2008 or 2012. A majority of the state’s votes come from Maricopa County, where Phoenix is. The basic rule in Arizona is that a lot of the early vote gets counted first, and it usually leans more Republican than the final result. In the state’s 2012 race, Republican Jeff Flake led Democrat Richard Carmona by 5 percentage points the morning after the election. Flake ended up winning, but by only 3 percentage points.

Colorado: Clinton has led in most surveys in the state thanks to strong numbers around Denver. And she probably needs to win Colorado to win the presidency. The state now votes mostly by mail. This is the first presidential election in Colorado to be held under these rules, so it’s a little tricky to know how quickly results will come in, and from where. Back in 2014 (the first major election using the new mail-in ballot rules), Republican Senate candidate Cory Gardner jumped out to a lead of more than 5 percentage points. He ended up winning by only 2 points as more votes cast closer to Election Day were counted. If that pattern holds, Trump will probably do better in the initial vote count but lose in the end.

New Mexico: Clinton will probably win here. She hasn’t trailed in any recent polls. Still, the polls are a bit closer than some may have expected at the beginning of the campaign. Clinton needs large margins in Santa Fe County and Bernalillo County (home to Albuquerque) to offset Trump’s lead in many rural areas. In both 2012 and 2014, the early vote (combined with absentees) was a bit more Republican than Election Day voting. If that holds, Clinton’s lead is likely to climb as the evening goes on.

Wisconsin: This is another state with a close presidential and Senate race. Clinton has never trailed in the state, despite her troubles in Iowa (just southwest of Wisconsin). Trump’s big problem is that voters in traditionally conservative Milwaukee suburbs just won’t support him by a large enough margin to wrest the state away from Clinton. The story is different in the Senate race, where Republican Sen. Ron Johnson is hoping to make a comeback against Democrat Russ Feingold. Like Clinton, Feingold holds the advantage, albeit a smaller one. The Republican suburbs around Milwaukee tend to report first, so the Republican candidates should do better in the early returns than in the final tally. If Johnson or Trump manages to win this state, it’s a sign of big trouble for the Democrats in the Senate race or the presidential election, respectively.

10 p.m.

Iowa: This used to be a key swing state, but this year it looks like Iowa is going to cast its votes for Trump. The best poll in the state (the Des Moines Register survey) had Trump up 7 percentage points in its final poll before the election, released this past weekend. White voters without a college degree appear to be leaving the Democratic Party in droves, and there are a lot of them in Iowa. Beware, though: Iowa early voters traditionally lean Democratic, so Clinton could be up with a lot of the vote counted and still lose the state. Back in 2014, Republican Senate candidate Joni Ernst trailed by 7 percentage points with 30 percent of the vote counted. She ended up winning by more than 8 percentage points.

Nevada: This could be the key state for determining who wins the presidency and the Senate. If Clinton wins it, she can become president without taking Florida, New Hampshire, North Carolina and Ohio. Meanwhile in the Senate race, Democrats are looking for Catherine Cortez Masto to hold Harry Reid’s seat against a strong challenge from Republican Joe Heck. The polls have shown a close race in the Senate and presidential elections, but the early vote statistics suggest that both Democrats will win. Since the majority of the vote is cast early, it should be counted fairly quickly. Keep in mind that it’s really all about Clark County (Las Vegas) in Nevada. The majority of the vote is cast there, and Democrats traditionally carry it. If Clinton and Cortez Masto win it by 10 percentage points or more, they’ve probably got it.

Utah: There hasn’t really been a competitive presidential race in Utah in a long while, so there are no clear benchmarks. That’s especially the case because independent candidate Evan McMullin should have a strong showing. Although no candidate is expected to come close to a majority of the vote, Trump still leads in the polls. For Clinton to win, she’ll probably need to win in Salt Lake City (in Salt Lake County) and Park City (Summit County) by wide margins. Meanwhile, McMullin will have to do well in the rest of the state, where the Mormon share of the population is larger. Trump will probably need to beat McMullin in Mormon areas, as well as hold his own where Clinton wins.

11 p.m.

California, Hawaii, Oregon and Washington: Democrats should easily carry all four states. But I highlight them because if Clinton does what we expect her to do in other states, then the election could be called for her when these polls close. That’s what happened for Obama in 2008. In 2012, it took until about 11:15 p.m. for the race to be called for him.

1 a.m.

Alaska: This is the last state to close its polls. Yes, the presidential race is likely to be decided by the time Alaska returns start coming in, as is the Senate. Still, Clinton’s trailing by far less in the polls than Obama ended up losing by in 2012. But she’s still well behind Trump. If the race in Alaska is at all close, determining the winner will take days because the state is slow to count absentee and early votes. It took a week to determine that Republican Dan Sullivan had won the state’s U.S. Senate race in 2014, when he prevailed by 2 percentage points.