Although more than 160 million Americans voted in the 2020 election, the outcome was ultimately decided by tens of thousands of votes in a small handful of states. Things could get even tighter in 2024.

According to a recent CNN analysis of the current math of the Electoral College, there are only a few narrow paths to victory for either President Joe Biden or former President Donald Trump. To win the election, a candidate must win 270 electoral votes, and most states are heavily tilted toward one candidate or the other. The most competitive swing states like Arizona, Florida, Georgia, Michigan, Minnesota, Nevada, North Carolina, Pennsylvania, Virginia and Wisconsin will determine the winner.

An expert told the network that voters’ opinions are already largely set in stone and that the election will therefore likely depend on which campaign is most successful in turning out voters in the final months before ballots are cast.

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“I still think this is a race where we’re not going to see the polls move outside of a pretty narrow window,” GOP pollster Kristen Soltis Anderson told the network. “If you liked Donald Trump last week, you’ll still like him this week. If you liked Joe Biden last week, you’ll still like him this week.”

2020 offers the latest example of how a few thousand votes in a few counties in a few states can sway an entire election. In Arizona, for example, Biden won the state by fewer than 11,000 total votes. He won Georgia by fewer than 12,000 votes. And he won Wisconsin by fewer than 21,000 votes. Those three states, combined with Nebraska’s 2nd congressional district (Nebraska and Maine distribute electoral votes by congressional district), are what decided the Electoral College for Biden.

Similarly, Trump’s victory over Hillary Clinton in 2016 came by fewer than 78,000 votes in the three so-called “blue wall” states of Michigan, Pennsylvania and Wisconsin. The combined 46 electoral votes from those three states enabled Trump to win the presidency and appoint Justices Amy Coney Barrett, Neil Gorsuch and Brett Kavanaugh to the Supreme Court — who then helped to Roe vs. Wade in 2022 and grant presidents absolute immunity from criminal prosecution in the recent Trump vs. the United States decision.

In 2024, CNN’s analysis found that 152 electoral votes are up for grabs in 12 states that flipped from Republican to Democratic or Democratic to Republican in the 2016 and 2020 elections. More recently, states seen as solidly Republican, like Florida and Ohio, have become competitive for Democrats due to high-profile Senate races and ballot questions. And states previously considered safe for Democrats, like Minnesota and Virginia, are now in play for Republicans as doubts persist about Biden’s viability as a candidate.

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While both presidential campaigns will spend large sums on voter education and advertising, it is other non-candidate issues in key states that could boost turnout. Florida, for example, has an abortion rights ballot initiative on the ballot in November. As a result, more recent polls show that female voters are leaning toward the Democratic ticket.

Other swing states with ballot measures include Ohio, where voters will decide whether to have a citizen-led redistricting commission after each new census (Ohioans voted last fall to enshrine abortion rights in their state constitution). And in Arizona, there are numerous ballot initiatives up for vote in November on a variety of issues, including pay for tipped workers and term limits for Supreme Court justices, among others.

Click here to read CNN’s full analysis.

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