Residents vote at an in-person early voting location in the Kenosha Municipal Building on October 24 in Kenosha, Wisconsin.

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CNN  — 

For the vast majority of Americans who live outside the seven battleground states, there is a confounding helplessness in 2024.

On the one hand, polling suggests a historically tight race heading into Election Day.

On the other hand, the Electoral College map suggests that the results in all but those seven states are a foregone conclusion, assuming people show up and vote the way polling suggests they will.

Every vote counts, obviously, but some seem to matter more than others. At least in some years.

Swing today, safe tomorrow

If there is some consolation for the millions of Republicans in California and Democrats in Texas – and so on – it is that today’s swing state is tomorrow’s safe state.

Missouri, for example, is a flyover state for presidential candidates today, reliably red and far off the radar of campaigns popping back and forth between actual battlegrounds.

But for about 100 years, Missouri was the ultimate bellwether in presidential elections, voting for the winner in 25 of 26 elections between 1904 and 2004 – within the lifetime of most of today’s voters.

Florida and Ohio, both of which are now red states for presidential purposes, were hotly contested battlegrounds until this election cycle. Virginia and Colorado, which were battlegrounds in roughly the same era, are now essentially blue in presidential years.

In the closest possible election that people alive today can remember, 2000, it’s Florida’s “hanging chads” and the US Supreme Court decision that ended a recount there that stick in people’s minds. But New Hampshire and New Mexico, now both blue states, were also decided by the smallest of margins.

Battlegrounds for about a generation

The point is that the people and politics of this country are constantly churning and moving. The makeup of the battlegrounds seems immutable in a single election, but battlegrounds have a shelf life, and it might only last about a generation.

I talked to David Schultz, a political science professor at Hamline University and author of the book, “Presidential Swing States,” which will be due for its fourth edition after the 2024 presidential election.

Swing, battleground and competitive are different things

Schultz told me that while we use terms like “swing state” and “battleground state” interchangeably, they’re actually different things.

A swing state is one that has actually flipped and recently supported presidents from different parties. Think of the “blue wall” states of Pennsylvania, Wisconsin and Michigan. They swing from Democratic President Barack Obama in 2012 to Republican President Donald Trump in 2016 and then back to Democratic President Joe Biden in 2020.

Now they’re battleground states, or places where candidates show up and campaign.

They also fall into a third category of competitive states, where results are within 5 percentage points.

“In many cases, a swing state is really all three. It’s a battleground state. It’s been flipped. It’s competitive. But in some cases, there are states that have not flipped yet,” he argued.

More technically, according to Schultz, these states usually share some characteristics, including that they are relatively evenly split between Republicans and Democrats and that their “average or median voter is to the right of where the Democrats are nationally and to the left of where the Republican Party is nationally.”

Today’s battlegrounds

That’s about where the Rust Belt states collectively known as the blue wall are at the moment.

They had voted in a bloc for Democrats in every election from 1992 until Trump won them in 2016. They moved back toward Democrats in 2020 and represent Democrats’ best chance to retain the White House, according to many political strategists, even though the long-term demographic trends might not be so favorable for Democrats there. The parties are increasingly divided by education and race.

In Schultz’s view, if there’s one single bellwether state this year, it’s Pennsylvania.

Republicans are in a similar situation with Sun Belt states like Georgia and North Carolina, which have seen population growth among young people and people of color.

The country is constantly changing

Schultz argued that with deaths spurred by the Covid-19 pandemic, as well as internal migration and new voters being eligible to vote, some states have seen up to a 20% change in the makeup of their populations since just the last election.

That means the country’s population has changed quite a bit since some states last swung.

In the 1988 election, the last time the blue wall did not vote together, Pennsylvania and Michigan voted with the loser, Democrat Michael Dukakis. That election represented the end of an era in many ways. That was the last election in which California, the most populous state, voted for a Republican president, George H.W. Bush.

Texas, the second most populous state, on the other hand, hasn’t voted for a Democrat since Jimmy Carter won the White House in 1976, although results there were quite close in 1992 and 1996 when Clinton won the White House.

Schultz said the country has seemed to sort itself into red and blue and that something is shrinking the number of competitive states.

“If a state gets to be a reputation of being Republican or Democrat, we start to see patterns of immigration, of people sorting themselves out of where they want to live,” he told me.

Will Texas ever turn?

Democrats, for years, have been hoping that demographic shifts would again put Texas in play, something that could completely reshuffle the electoral map. Schultz doesn’t see that kind of shift in Texas for another four or eight years.

But he does think there are some states that could become new swing states in the years to come. He mentioned South Carolina and Montana, states that could shift as more young people move into them, changing their makeup.

If you look at all the competitive states in all the elections going back to 1976, most of the states have swung one way or the other or been competitive in the past 50 years.

Some states change all of a sudden

Sometimes, the swing bypasses the competitive category altogether.

West Virginia today is one of the most reliably Republican states – when it swung from Democrats to Republicans in the 2000 election, it swung hard. The result placed it outside the “competitive” category.

In other years, nearly the entire country swings, such as in 1984 – when the only state won by the Democratic candidate, Walter Mondale, was Minnesota, his home, which he took along with Washington, DC.