Both presidential campaigns descend on critical swing state of Pennsylvania

The US presidential candidates Donald Trump and Kamala Harris will hold dueling campaign events this weekend in the critical political battleground state of Pennsylvania.

The former president was due to hold a Saturday rally in Wilkes-Barre in the north-east of the state, while the vice-president is on a bus tour of western Pennsylvania starting in Pittsburgh on Sunday, before the Democratic national convention kicks off on Monday in Chicago.

Related: Democratic national convention: who are the politicians to watch?

Separately, Tim Walz, the Democratic vice-presidential candidate and Minnesota governor, was scheduled to hold a rally in La Vista, Nebraska, on Saturday.

According to an NYT/Siena College poll published on Saturday, Harris is now leading Trump among probable voters in Arizona by 50% to 45%, and North Carolina, 49% to 47%, while trailing narrowly in Nevada and in Georgia by a four-point margin.

But the three critical so-called Rust belt states, Pennsylvania, Wisconsin and Michigan, continue to preoccupy the rival campaigns, with Pennsylvania and its 19 electoral college votes considered key to both candidates’ chances of victory in November.

Since 2008, the trio have been reliable bellwethers of the outcomes of national elections. Pennsylvania’s electoral college votes, plus Michigan’s 15 and Wisconsin’s 10, are typically enough to put a candidate over the top in the race to secure the 270 total needed to win the White House.

The election forecaster Nate Silver calculates that Pennsylvania is more than twice as likely as any other to be the “tipping point” state for presidential victory this fall.

Both campaigns are on the hunt for support among white, non-college-educated voters, with the Harris-Walz ticket looking to shore up support among suburban voters and to drive up voter turnout in urban areas with large Black populations that Trump and his running mate, the Ohio senator JD Vance, are hoping to peel off.

Both campaign strategies are considered “win big, lose small” but with different focuses: for Democrats in Pennsylvania, that means looking for big margins in the cities and suburbs of Philadelphia and Pittsburgh, while limiting losses in rural parts of the state such as Beaver county, close to Butler, where Trump was shot by a would-be assassin last month.

Trump won Pennsylvania in 2016 by around 44,000 votes, a margin of less than one percentage point, while Biden prevailed by just more than 80,000 votes in 2020, a 1.2% margin.

Harris is leading Trump by more than 2% in the state, according to the forecaster FiveThirtyEight. Recent polls – by Quinnipiac and by the New York Times and Siena College – placed Harris three and four percentage points ahead, respectively, among probable voters in the state.

“The Trump campaign believes there’s still some juice left in that orange for them in the heart of north-east Pennsylvania,” Chris Nicholas, the Pennsylvania Republican consultant, told the Philadelphia Inquirer last week.

Saturday’s Trump rally will be in the indoor Mohegan Sun Arena with a capacity of around 8,000 people. The Trump campaign has said the candidate would return to Butler in October but a date has not been announced.

Pennsylvania is also the recipient of more campaign spending than any other battleground. The Wall Street Journal calculated that of more than $110m spent across seven swing states since 22 July, when Joe Biden dropped out of his re-election race, $42m has been funneled into the state.

Democratic and Republican political groups have also reserved $114m in ad time in Pennsylvania from late August to November – more than twice than planned for Arizona, the next highest, at $55m.

The Pennsylvania push is set only to intensify. Harris and Walz and their spouses will making stops across Allegheny and Beaver counties on Sunday, while Trump will respond to Harris’s recent economic policy proposals at an event in York, Pennsylvania, on Monday and Vance will be in Philadelphia.

And Pennsylvania will again be in focus when ABC hosts the first Harris-Trump debate in Philadelphia on 10 September.

Reuters contributed reporting