Three scenarios for how the US midterm results could unfoldDemocratic wave or Republican resilience? Here are three possible outcomes after Americans have their say. 1 hr agoUS & Canada

After months of campaigning and billions of dollars spent on the US midterms, election day is finally here.

According to the latest public opinion surveys, Democrats appear to have the upper hand – but polls haven’t always been reliable, and this year could have its own share of surprising results.

In broad strokes, however, there are three possible outcomes after Americans have their say.

Here’s a look at what they could be, what the early signs might be as results come in and what it could mean for the country.

If history is any guide, midterm elections tend to favour of the out-of-power party.

Add in what polls suggest is a historically unpopular president, a war with Iran that has driven up consumer costs and some controversial policies – like aggressive immigration enforcement and support for data centre construction – and you have the conditions for a so-called electoral wave.

In this first scenario, a huge wave is exactly what happens.

Democrats could not only take control of the House of Representatives but far surpass the 218 seats needed for a majority. They may win not only the dozen or so races that election analysts rate as too-close-to-call, they could also flip some seats in more solidly conservative terrain.

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In the Senate, this scenario would require Democrats to win all or most of the current crop of races that are toss-ups, including some in traditionally conservative states. There would be at least one eye-popping victory in a place that hasn’t elected a Democrat in a generation, Texas, or in nearly a century in the case of Kansas.

If this did happen, Democrats wouldn’t just take control of the Senate, they would do so with a seat or two to spare. This might avoid any drama around a potential legal challenge by Republicans in Alaska where a judge dismissed a Trump administration lawsuit over two Dan Sullivans being on the ballot.

Democrats might accomplish this by boosting turnout of their voters and winning independent voters by sizable margins. This would reverse Trump’s 2024 inroads with Hispanic voters and young men. Some Republican voters might also support the Democrats or just stay home.

This kind of a result would represent a stinging rebuke for Trump and his Republican Party, setting up two years of conflict between a newly invigorated Democratic Party with its hands firmly on the lever of legislative power and a president who seldom backs away from a fight.

Early signs as the results come in:

If Democrats hold targeted House contests in Florida and win some Republican districts in North Carolina, Michigan, New York, Virginia and Kentucky. If they flip the Senate seat in South Carolina, it’s going to be a good night for Democrats.

Maybe the polls won’t be entirely wrong, but not entirely right either.

In this scenario, it could be that while they take enough of the low-hanging fruit in the US House contests to deliver a majority, it’s not a sizable one.

This would mean Democratic leaders in the chamber would regularly have to wrangle with their fringe members on the left and the centre to ensure they have enough votes to pass legislation.

On the Senate side in this hypothetical, the Democrats would just flip a seat or two – North Carolina, for instance, seems all but assured – but the contests in the conservative heartland would prove to be out of reach.

Perhaps they’re unable to unseat stubbornly resilient Republican Senator Susan Collins in Maine or left-wing candidate Abdul El-Sayed can’t keep Michigan in the Democratic column.

Maybe the duelling Dan Sullivans controversy is enough to sink Democratic candidate Mary Peltola in Alaska.

For this “Democratic trickle” scenario to unfold, the big Democratic turnout we’ve seen in early voting would be matched by a Republican surge on election day.

Trump’s efforts to rally his base in Republican red states could help his party avoid the worst-case scenario. The races that were at or near the margin of error in polls might provide a mixed bag for both parties.

The result would be a divided Congress – and that’s a recipe for political gridlock.

Early signs as the results come in:

If Florida stays comfortably Republican across the board. If Democrats pick up some House seats in places like Virginia and Pennsylvania, but the Republican incumbents on more secure political ground across the country avoid getting washed away in a deluge.

This scenario involves Republicans resiliently holding on to both chambers of Congress.

For this to happen, the polls – which have previously underestimated Trump’s support – need to be wrong and the toss-up races to mostly fall the way of Republicans.

Not only would Republican voters have to turn out in unexpectedly impressive numbers, independent and Hispanic voters who had seemingly soured on Trump’s policies would have also to break his way in the end.

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In this scenario, control of the House, far from being a done deal for Democrats, could end up coming down to California and its extended days-long counting process for mail-in ballots.

In the end, Republicans might eke out a slim overall majority thanks in part to efforts to draw more favourable congressional district lines in places like Texas, Florida and North Carolina.

It could also be that Republicans win all the Senate contests in the conservative states and they also flip Michigan, a seat that was held by Democrats heading into the vote.

Even if Republicans don’t hold North Carolina or win in Democratic-controlled Minnesota or New Hampshire – races just on the periphery of competitiveness in this year’s elections – they may at least make the Democratic candidates sweat.

If this was to happen, Trump might on Wednesday morning would claim a renewed electoral mandate and push forward with his domestic and foreign policy agenda with the continued support of a Republican Congress.

Early signs as the results come in:

If Senators Ashley Moody in Florida and Jon Husted in Ohio cruise to re-election. If Republicans hold their own in House races in Pennsylvania and Virginia, and they flip current Democratic seats in North Carolina, Ohio and Florida.

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