Most of the final polls are well within the margin of error, both nationally and in the seven key battleground states where we will decide the election.

Based on statistics and sample sizes alone, we can say that one of the two candidates is ahead.

This uncertainty angers political pundits and campaign strategists.

There are several surprises, even a recent, respected poll of Republican-leaning Iowa gives Harris a surprising lead.

But the major polling averages and the forecast models we interpret all say it's a coin-flipping contest – anyone can win.

Just because the outcome of the election is uncertain and the actual result will not be decisive.

A shift of a few percentage points in either direction results in one candidate winning all contested states.

If the turnout models are wrong and more women vote, or more rural residents, or more dissatisfied young voters – that would dramatically change the final results.

There are also surprises among key demographic groups.

One question: Will Trump really get close to young black and Latino men, as I predicted during the campaign?

Harris getting fit and winning over a larger share of traditional Republican suburban women than her team hopes?

Older voters vote in every election and tend to switch to the Democratic column?

After choosing the rearview mirror, we were able to conclusively provide a reason why the winning candidate came out on top.

At this point things are obvious. But anyone who says they know how cans work is simply deceiving you – and themselves.

For most US states, the outcome of the presidential election is almost certain. But there are seven key battlegrounds where we will decide whether to vote out.

Not all contested states are the same. Each candidate is given a “wall” of three states that offer them the most direct path to the White House.

Harris' so-called “blue” wall, named after the color of the Democratic Party, stretches across Pennsylvania, Michigan and Wisconsin in the Great Lakes region.

This has been the subject of much political conversation since 2016, when Trump narrowly won all three traditionally Democratic states en route to victory.

Joe Biden returns these states for 2020. If Harris can hold it, she won't need another battleground as long as she also wins a congressional district for Nebraska (there is a different system for allocating electoral votes).

That explains why she didn't spend much time on these blue wall states during the final campaign phase, spending full days on the ground for each one.

On Monday night, she held her final rally for Philadelphia, Pennsylvania, at the top of the 72 steps that lead to the city's art museum, where Sylvester Stallone's fictional boxer Rocky posed for the film of the same name – and narrowly lost to his opponent, Apollo Creed.

Trump's “red wall” is located on the eastern edge of the USA. Although you haven't given it much thought, it is equally important for my election chances.

E begins in Pennsylvania but extends south to North Carolina and Georgia

If we carry these states, we will win by two electoral votes, no matter how the electors vote.

That explains why we held five events for North Carolina last week.

The overlapping point on each of these walls, of course in Pennsylvania – the biggest electoral victory on the battlefield.

The nickname, the Keystone State, couldn't be more appropriate.

Sometimes it's important that they all plan and strategize their election plans – and that these presidential elections are historic

Harris and Trump represent two very different views of the United States – on immigration, trade, cultural issues and foreign policy.

Over the next four years, the president will be able to shape American government—including the federal courts—so that it remains effective for generations.

The U.S. political landscape has not changed dramatically over the past four years, but rather reflects changes in the demographic makeup of both parties.

The Republican Party of a decade ago looks very different from the populist party led by Trump, far more attractive to working-class and low-income voters.

The Democratic Party's base still relies on young voters and voters of color, but it now relies more on wealthy people with college degrees.

Tuesday's results provide additional evidence of how American politics is changing and changing the U.S. political map.

And these adjustments give one side an advantage for future races.

Not long ago—in the 1970s and 1980s—Republicans were viewed as a party that won the presidency because they consistently won a majority for enough states to advance to the Electoral College.

This election might be a 50-50 contest, but that doesn't mean it's a new normal for American presidential politics.