The US presidential election remains on a knife-edge 45 days before voters go to the polls, despite Kamala Harris enjoying one of her most encouraging spells of opinion polling since becoming the Democrats’ nominee nearly two months ago.
During yet another momentous week that began with a suspected second assassination attempt against Donald Trump, the latest Guardian 10-day polling averages survey shows Harris increasing her lead to 2.6 points, 48.5% to 45.9%.
While still within error margins, that is an improvement of the 0.9% edge Harris held last week and a significant shift from the statistical dead heat of a fortnight ago before the candidates held their only scheduled televised debate in Philadelphia on 10 September.
Polling suggests voters, by large majorities, believe Harris won that encounter – when Trump, the Republican nominee and former president, effectively self-sabotaged by going on off-topic digressions about crowd sizes at his rallies and making universally debunked claims about Haitian immigrants eating pets.
A New York Times/Philadelphia Inquirer/Siena nationwide poll on Thursday showed the candidates tied at 47% – actually a slight improvement for Harris on the same survey taken before the debate, when Trump recorded a one-point lead.
Other national polling has been more positive for Harris. A Morning Consult poll – based on more than 11,000 respondents – gave her a six-point advantage, 51% to 45%, the biggest she had established since replacing Joe Biden at the top of the Democratic ticket.
There are other underlying trends giving Harris reasons to be cheerful, albeit cautiously.
One is her buoyant performance in battleground states, the key arenas in determining the result of the 5 November election under America’s electoral college system.
The same New York Times/Siena poll that had the two candidates deadlocked nationally showed Harris with a four-point advantage, 50%-46%, in Pennsylvania, a swing state that many commentators identify as the most important of all in reaching the 270 electoral votes needed to capture the White House.
The survey is supported by a separate poll from Quinnipiac, which shows Harris with a six-point lead in the state, 51% to 45%
Moreover, the Quinnipiac poll gives Harris leads in two neighbouring battlegrounds, Michigan and Wisconsin, 5% and 1% respectively.
Capturing all three states – sometimes termed the “blue wall” by Democrats – would be enough to secure Harris a tiny electoral college victory without her needing to win any of the four southern Sun belt states (North Carolina, Georgia, Nevada and Arizona), where the two candidates are statistically tied.
Yet amid the optimism, there is a note of caution for the vice-president; Trump significantly over-performed pollsters’ predictions in the blue wall states in the last two elections, capturing all three in 2016 and losing each by around a single percentage point in 2020, when polls had put Biden much further ahead.
Nevertheless, pollsters detect a change from previous elections that is working in Harris’s favour – and which is whittling away the Republicans’ assumed advantage in the electoral college, where Trump won in 2016 despite receiving 2.7m fewer votes nationwide than Hillary Clinton, his opponent.
Nate Cohn, the New York Times’s chief polling analyst, called Harris’s lead in Pennsylvania while tying with Trump nationwide “a puzzle” but said it was consistent with most other surveys.
“Over the last month, a lot of these polls show Ms Harris doing relatively poorly nationwide, but doing well in the Northern battleground states,” he wrote.
“What’s clear is that recent results from higher-quality polls are very different from those of the last presidential election. If true, it would suggest that Mr Trump’s advantage in the Electoral College, relative to the popular vote, has declined significantly since 2020.”
Harris has one other apparent reason for self-congratulation; the deficit with Trump over which candidate is trusted on the economy has been closed.
The economy remains the single biggest issue in the eyes of most voters, surveys show – recalling the mantra “it’s the economy, stupid” coined by James Carville, the Democratic operative who helped chart Bill Clinton’s 1992 election victory.
Yet the large lead Trump held over Biden – amid persistent concerns over inflation and rising living costs – seems to have eroded since Harris was nominated, separate surveys show.
An Associated Press-Norc poll published on Friday showed 41% of voters trusted Harris as a steward of the economy, while 43% gave Trump the nod – a nominal gap given the ex-president’s attempts to tar his opponent with Biden’s unpopular economic record.
The results bore out an earlier Morning Consult study, which tied the candidates at 46% on economic trust, while an FT-Michigan Ross survey conducted after the debate even gave Harris a small lead.
Sofia Baig, an economist and author of Morning Consult’s study, said Harris had successfully evaded blame for Biden’s policies while winning over voters with her pledges to crack down on price gouging and prescription drug costs.
“While many voters are unsatisfied with the current economy, they say Vice President Kamala Harris is less responsible than President Biden,” she wrote. “Throughout this election cycle, voters consistently said they trusted former President Trump over Biden to handle the economy, but Harris has closed that gap.”
