US election heatmap: Unpacking Trump and Harris’s battle for the White House

Every election depends on campaigning, but maybe none more so than the US presidential election. A handful of so-called ‘swing states’ are pivotal to deciding the outcome – one that has been nail bitingly close in the past. 
In this new segment, updated every two weeks, Tony Diver, US editor, and Meike Eijsberg, data journalist, will dive into the candidates’ campaigns. 
These insights will offer answers to questions like: What effect will Kamala Harris’ latest interview have? Why is Donald Trump campaigning in a state he’s won previously? What is happening online? How are the candidates getting donations to fund their campaign and are they succeeding at it? 
Kamala Harris and Donald Trump have continued to blitz through a handful of swing states, as well as the midwestern USA’s ‘Rust Belt’ in the lead-up to Labor Day on Sept 2.
Since last weekend, both presidential contenders visited Michigan and Pennsylvania, while Trump also held events in Arizona and Nevada, and Ms Harris rallied supporters in Georgia.
Polling shows that Harris has a narrow route to the White House via the three swing states of Wisconsin, Pennsylvania and Michigan, even if she cannot overturn Mr Trump’s lead in Arizona. The pair are tied in Nevada. 
Trump’s route to power likely involves wins in the Sun Belt, which includes Arizona, Nevada and Georgia. He is also narrowly ahead in North Carolina, a swing state he won in 2020.
Joe Biden carried Pennsylvania by fewer than 90,000 votes in 2020 and, according to FiveThirtyEight, Harris is currently leading Trump by a margin of 1.5 per cent.
Both of the candidates’ running mates also made trips to states that are not on the list of seven battlegrounds, including a visit to Maryland for Tim Walz and Kentucky for JD Vance.
While Ms Harris and Mr Walz were at the Democratic Convention in Chicago, Mr Trump and Mr Vance were hopping across the country. In just seven days, they ticked off every single swing state.
One of the Republicans’ first stops was a joint rally in Asheboro, North Carolina. The state was narrowly won by Trump in 2016 and 2020, but recent polls show both presidential hopefuls as neck and neck.

The Republican campaign will need to shore up support amongst even the most ardent supporters and Randolph County, where Asheboro is located, epitomises these efforts. One of the reddest in the state, more than three quarters of its voters supported Trump in both elections.

For the Democratic campaign, the Harris and Walz Georgia bus tour highlights how much the campaign has moved on since Biden’s resignation. Back in July, Trump led Biden by 4 points in the state. Now Harris believes she can retain Georgia, which was won by Biden by just 0.23 per cent – the smallest margin that cycle.

One factor plays in her favour: Georgia has the third largest population of African-Americans in the country, a group Harris is currently polling favourably with. Around 78 per cent of black voters are planning to vote Democrat, an August poll from Siena suggests, up from below 60 per cent in July.

Since Biden stepped down on July 21, Harris has spent more than 12 times as much on Google and Meta ads as Trump.

High ad spending tends to go hand in hand with specific targeting. The Harris campaign is attempting to capture the attention of voters who may not have previously considered supporting the Democrats.

Both Trump and Harris are heavily targeting swing states online, with Pennsylvania – the battleground with the highest number of electoral votes – receiving the highest proportion of their ads.

Meanwhile, vice presidential candidates Mr Walz and Mr Vance are spending their budget on “safe” states. A quick look at their ad content reveals why: they are specifically targeting existing supporters for campaign donations.

Overall, Harris has raised more money than Trump since she became the Democratic candidate. She also receives a greater number of donations per day, with a peak on the day she became the presumptive candidate.

In the swing states, it’s a different story. In dollar terms, Trump is raising more than Ms Harris in Arizona, Georgia, and Nevada. In terms of individual donations, Trump has more than twice as many as Harris in four out of seven swing states. This suggests that Trump has a lot of grassroot support whereas Ms Harris is dependent on fewer, but wealthier backers.

This article will be updated every two weeks with the latest information.