The winner of the US presidential election will govern a nation of more than 330 million people, but the contest could be decided by just tens of thousands of voters in a handful of states.
The president is not decided solely on the popular vote. Instead, under the Electoral College system, the winning candidate in each state and Washington, DC, receives that state’s electoral college votes, which are largely based on population.
There are 538 members of the Electoral College, meaning a candidate must get 270 electors (one more than half) to win the presidency.
All states except Maine and Nebraska have a winner-take-all policy, meaning whoever wins the state’s popular vote gets the entirety of its college votes. The system means a candidate can win the popular vote, as Hillary Clinton did in 2016, but then lose the election on the Electoral College count.
Opinion polls suggest that only seven of the 50 states are truly competitive this year. The rest are all comfortably Democratic or Republican. The seven states that could swing either way are the Rust Belt trio of Michigan, Pennsylvania and Wisconsin and the Sun Belt quartet of Arizona, Georgia, Nevada and North Carolina.
If we allocate the Electoral College votes to all the states that polling suggests are already decided, then Harris has 226 votes and Trump 219, leaving 93 Electoral College votes up for grabs from those seven states.
There are 71 different combinations from those seven states that could give Harris the 270 needed, and 54 for Trump.
Here, we look at seven possible scenarios to watch out for on Wednesday AEDT.
Through much of this campaign, Harris has led the polls in the key states of Wisconsin, Michigan and Pennsylvania, and claiming all three would give her exactly 270 seats and her most straightforward path to victory. These three states, the “blue wall” or “Rust Belt”, will be crucial to either Trump or Harris winning.
Trump could also win the election with exactly 270 votes should he win three states in the eastern half of the country: Pennsylvania, North Carolina and Georgia. He has had strong polling in Georgia, and he won North Carolina in 2016 and 2020. Pennsylvania is a bit more of a battle, although the most recent New York Times/Siena polling has the state at 50/50. This result would give him 270 to Harris’ 268. Trump would also need to hold on to the single electoral vote in Maine’s 2nd Congressional district. Maine is a state that divides electoral votes by districts rather than granting them on a winner-takes-all for the state.
Harris could repeat Joe Biden’s victory of 2020 by retaining the Rust Belt and holding Georgia, Nevada and Arizona. In this case, Harris would win 303, while Trump, supposing he holds North Carolina, would claim 235. The latest battleground polling, however, has Harris behind Trump by four points in Arizona and Wisconsin.
In this scenario, Trump wins some key Sun Belt states – Nevada, Arizona, North Carolina and Georgia, a geographical region comprising the south-east to the south-west. But doing so would leave him agonisingly close on 268, meaning he would require victory in one of the Rust Belt states, such as Wisconsin.
Could history repeat itself and have Trump replicate the same path that gave him victory in 2016? To do so he’d have to win a patchwork of Rust Belt, southern and western Sun Belt states. The latest battleground polling has him ahead only in Arizona of those states he won in 2016, although he is even with Harris in Michigan and Pennsylvania. In this scenario, Trump would win 306 to 232 for Harris.
Trump wins three crucial Rust Belt states but Harris wins the Sun Belt, including Arizona, Nevada, North Carolina and Georgia. She currently leads in the battleground polling in three of those four.
Both Harris and Trump win 269 electoral college votes. This could happen if Harris wins three Rust Belt swing states: Wisconsin, Michigan and Pennsylvania, while Trump wins Nevada, Arizona, North Carolina and Georgia.
In this case, the newly elected members of the House of Representatives would vote to elect the president, with each of the 50 state delegations casting one vote. While there is a legal process for this, given the unpredictable nature of the election so far, a presidential election decided by Congress would most likely mark a new chapter of contest and uncertainty.
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