Kamala Harris breathed new life into the White House bid of the Democratic Party. Enthusiastic donors and supporters followed. Whether their excitement can last until November remains uncertain.

When Harris entered the 2024 race last month, she immediately began to attract record-high funding to her campaign and a groundswell of support on a still tight race to the White House.

On July 21, US President Joe Biden dropped his re-election bid and endorsed Harris as the Democratic Party’s presidential nominee, igniting a social media firestorm.

A surge in individual contributions quickly followed, helping Harris’ campaign raise around $130 million in July alone, almost five times the $27 million raised by her Republican rival, former President Donald Trump, an analysis of data from Federal Election Commission (FEC) showed.

The data only covers itemised contributions submitted to the FEC. Contributions must be itemised when they surpass $200 within an election cycle, according to FEC rules.

A streamgraph showing daily fundraising totals for the Democrats’ and Republicans’ presidential campaigns for July 2024. After Biden dropped out of the race and endorsed Harris, the Democrats saw a surge of donations dwarfing donations from either side in the previous month.

Enthusiasm over Harris has been palpable from the start. Democratic political action committee ActBlue posted its highest donations in 24 hours after Harris started her presidential campaign. In total, the Harris campaign said it raised around $500 million during its first four weeks.

Streaming of the show VEEP increased over 350 per cent in the days following Harris’s announcement to enter the presidential race, according to the entertainment insight company Luminate.

Harris is not only leading in campaign money. Polls indicate Harris has notched a significant improvement in harnessing the electorate than her predecessor. Before Biden dropped out, he was consistently underperforming Trump, but polls were still largely within the margin of error. The race remains close with no clear frontrunner, but some polls where Biden used to trail Trump have reversed and now show Harris currently outpacing her rival.

The US vice president is leading Trump among Black and Hispanic voters. She also captures more support from young voters.

President Biden had been slightly behind in the polls for months and the gap widened in the last three weeks before he decided to drop out of the race. Vice President Harris began her race and polls have been favourable for her, showing a lead in national polling against Trump.

But swing states are where elections are won and lost. Reuters has identified seven states as playing an outsized role in determining the winner of the presidential election and their electoral college votes could go either way. Six of the seven have had enough polls conducted to calculate an overall trend for each candidate and tell the story of a very close race. Nevada did not have enough data.

The polls have been gaining datapoints, but the wide swings indicate a lack of stability in the trendlines at this point.

Chauncey McLean, who heads the super political action committee Future Forward, said there was a significant shift in political momentum following Biden’s withdrawal. As president of a super PAC that has channelled hundreds of millions into Harris’ campaign for the November 5 election, McLean said the surge in support has largely come from young voters of colour. This demographic boost has revitalised Democratic prospects in key Sunbelt states such as Nevada, Arizona, Georgia and North Carolina, states which Democrats had largely written off in the final days of the Biden campaign.

McLean said Pennsylvania remains the most consequential state in the group’s analysis and he called the race a “coin flip” based on its polls. He says Harris must win one of three states – Pennsylvania, North Carolina or Georgia – to win the White House.

He warned that Harris has yet to fully rebuild the Biden coalition of Blacks, Hispanics and young voters that brought him the White House in 2020.

The Harris camp is aware the optimistic polling may not be an accurate reflection of reality. “Our numbers are much less rosy than what you’re seeing in the public,” said McLean.

• A Reuters report