Electoral math: Biden needs to take these swing states to win in 2024

As the November election approaches, U.S. presidential campaigns are focusing on crucial swing states that will decide the winner of the White House. In a fiercely contested rematch between President Joe Biden and former President Donald Trump , both candidates have little margin for error.

While the popular vote is significant in a presidential election, the key to victory is securing 270 electoral votes (out of 538), and this year's projections indicate a tighter race than 2020.

More: How do electoral votes work? What to know about the voting process

How does the Electoral College work?

The Electoral College consists of 538 votes split among the 50 states. Each state gets points based on the members of its congressional delegation: one for each U.S. Representative and two for the U.S. Senators.

For the 2024 election, Arizona, Georgia, Michigan, Nevada, Pennsylvania, and Wisconsin are crucial battleground states that both Democrats and Republicans need to win to secure the 270 electoral votes required for the presidency.

If Trump takes any of the Rust Belt states —specifically Wisconsin, Michigan, or Pennsylvania—in November, it does not bode well for Biden. With less than 20 weeks until Election Day, political operatives on both sides say it's a make-or-break for the respective campaigns.

"That's the must-have," said Faiz Shakir, a Democratic strategist who managed Bernie Sanders' 2020 presidential campaign, to NBC News .

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In 2020, states including Georgia, Arizona, and Nevada helped deliver a significant bundle of electoral votes to Biden, who came out with 306 points compared to Trump's 232. However, with recent polling showing Trump leading the president in the Sunbelt states and Georgia, the most straightforward path to the White House for Biden is through the Midwestern "blue wall."

What is the "blue wall?"

The "blue wall " consists of swing states that hug the Great Lakes, including Wisconsin, Michigan and Pennsylvania. If Biden can manage to hold up the wall as he did in 2020, he could still win the election, even if Trump takes Arizona, Georgia, and Nevada.

The 2020 census is making it tricky for the Democrats. Thanks to a recent population decline in the Great Lakes region, Biden effectively lost three electoral votes from states he won that year — including one each from Michigan and Pennsylvania — and moved them into states that favored Trump. That's where Nebraska, specifically Omaha's 2nd Congressional District , comes into focus.

Why are Biden and Trump eyeing Nebraska?

Unlike the rest of the 48 states, which have a winner-take-all system in which the candidate with the popular vote gets all of a state's points, Nebraska and Maine have a unique split vote system. In this system, points are divided between candidates based on who wins individual congressional districts.

For example, Nebraska has five electoral points and three U.S. House seats. The winner of the popular votes gets two electoral points, and the other three are awarded to the winners of each district, which is why both sides are eyeing the Cornhusker State .

It's possible the 2024 election could come down to that single House district , in which two Democrats and two Republicans won once in the last four election cycles.

This article originally appeared on USA TODAY: Electoral math: Biden needs to take these swing states to win in 2024