US Election 2024: Why is Pennsylvania so important for Kamala Harris and Donald Trump?

• Election could come down to who wins the Keystone State

• But why is Pennsylvania so important in US election 2024?

• Trump says if he wins PA he wins presidency

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Donald Trump and Kamala Harris may disagree about many things but one area where there is consensus between the US presidential candidates is that whoever wins Pennsylvania on 5 November is probably heading for the White House.

Trump told supporters at a rally in the state: "If we win Pennsylvania, we win the whole thing."

Betfair politics expert Paul Krishnamurty said earlier in the campaign: "If one state is set to determine the presidency, Pennsylvania is it. Without it, a Harris win becomes extremely unlikely. And whilst Trump has more paths, they aren't likely without it."

Pennsylvania has an important place in American history. The Declaration of Independence was approved by the Second Continental Congress at the Independence Hall (previously known as the Pennsylvania State House) on July 4, 1776.

And it has already been the scene of the one of this election's major moments.

On 10 September, Harris and Trump were in Philadelphia to take part in their only debate of the campaign. Harris was widely seen as the winner and flipped the odds becoming the odds-on favourite on the Betfair Exchange to win the election while Trump drifted to outsider status.

With just under six weeks to go before election day, Harris is still the favourite in the election winner market on the Betfair Exchange. The race is tight, however, and what happens in the aptly-named Keystone State will be crucial.

Pennsylvania is the ultimate swing state in 2024

Of the seven swing states, which could go Republican red or Democratic blue on election night, Pennsylvania looks set to be the most important - or the swingiest if you will. Both Harris and Trump are spending a lot of time there and if you happen to live in the state you probably cannot escape from the election.

Pennsylvania has 19 electoral college votes, all of which will go to the winning candidate on 5 November. That is more electoral college votes than any of the other swing states, although by no means the most electoral college votes of any state. California has the most with 50 but there is no question who is going to win there (the Democrats are heavy odds-on.)

Which way does Pennsylvania usually vote?

Pennsylvania has tended to back the winner in US elections. Only three times at elections between 1933 and 1988 was a candidate for president able to win without carrying Pennsylvania.

At the last election, in 2020, Joe Biden won the state by about 1.16 percentage points (80,555 votes), although it was not the state with the smallest margin - that was Georgia which Biden also won in 2020 but which Trump is 5/81.62 to win in 2024.

Four years ago, Pennsylvania had 20 electoral college votes but the allocation has since been ammended to reduce the Keystone State to 19. That has done nothing to reduce its significance.

If Trump can win all the states he won in 2020, and flip Georgia and Pennsylvania, he will get the 270 electoral votes that he needs to win the election.

Without Pennsylvania, his task becomes much harder and he will need to flip a minimum of three states.

If Harris wins Pennsylvania, Trump will need to flip Arizona, Wisconsin and Michigan. Harris is odds-on to win Wisconsin and Michigan. Harris also believes she can win in Georgia even though the Democrats are 6/42.50 there.

But Trump has won Pennsylvania before and would probably not be running for office if he did not believe he could turn this traditionally blue state red again.

In 2016, he became the first Republican since George H.W. Bush to win Pennsylvania. Once that result came in eight years ago it was clear that Trump, not the favourite Hillary Clinton, would win the presidency.

Then again, Harris was part of winning ticket with Biden in Pennsylvania in 2020, so she is convinced that she knows what it will take to win there in 2024.

At the last two elections then - those which took place when Trump was the Republican candidate - Pennsylvania has voted for the winner and it would be a surprise if it did not do so again.

Who will win Pennsylvania in 2024?

With just under six weeks to go the picture in Pennsylvania broadly resembles the national picture.

The Democrats are 5/61.84 and the Republicans are 11/102.11 to win the Keystone State.

This is in line with most polls which give Harris a small lead there.

Harris' pathway to the White House is much clearer with Pennsylvania than without it and the same is true for Trump.

Both believe they can win Pennsylvania on 5 November and both are going to be relentless in their pursuit of votes there all the way to election day.

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