Nearly two-thirds of Americans say they are not better off financially than they were when Donald Trump was elected, casting doubt on whether economic expansion and a record bull market will boost the president’s re-election campaign in 2020.

According to a poll of likely voters conducted by the Financial Times and the Peter G Peterson Foundation, 31 per cent of Americans say they are now worse off financially than they were at the start of Mr Trump’s presidency. Another 33 per cent say there has been no change in their financial position since Mr Trump’s inauguration in January 2017, while 35 per cent say they are better off.

Persistently slow wage growth appeared to be a main driver of discontent, with 36 per cent of those who said they were worse off blaming their income levels. On Friday, the US labour department said average hourly income had risen 3 per cent in October, growth that was near highs for the past decade but lower than before the financial crisis. Another 19 per cent pointed to personal or family debts as the reason they felt worse off.

The FT-Peterson poll’s findings underline the challenges facing Mr Trump, who is relying on his stewardship of the economy as a main argument for his re-election. The president has repeatedly touted stock market records and robust job creation as his administration’s most important accomplishment, and has angrily blamed the US Federal Reserve for any signs of economic weakness.

Last week, after the latest US economic data showed gross domestic product had expanded by 1.9 per cent in the third quarter, Mr Trump said in a tweet: “The Greatest Economy in American History!”

The poll suggests the economic expansion and financial market rally of the Trump presidency have buoyed perceptions of only a narrow segment of the American electorate. College-educated men, for instance, were most likely to feel better off now than they were when Mr Trump first became president, with 48 per cent saying their fortunes had improved.

The FT-Peterson US Economic Monitor, which will be conducted monthly until the November 2020 election, shows the nation is sharply divided over Mr Trump’s economic policies, with 45 per cent saying they have helped the US economy and 45 per cent saying they have hurt. Mr Trump’s tax cuts for companies and the wealthiest Americans, as well as his focus on deregulation, have been hallmarks of his presidency.

The results showed party affiliation was a key driver in whether voters back Mr Trump’s economic agenda, with just 10 per cent of Democrats saying the president’s policies have helped, compared with 84 per cent of Republicans.

Larry Sabato, director of the University of Virginia’s Center for Politics, said that while economic sentiment has traditionally played a major role in US elections, 2020 is likely to prove an exception given such high levels of partisanship.

“There are exceptions. When there is a war going on, the war takes precedence over the economy. When there is a scandal going on, the scandal can take precedence over the economy,” said Mr Sabato. “In this case, Donald Trump the person will take precedence over the economy.”

When asked what was the biggest threat to the US economy, 27 per cent of poll respondents pointed to trade disputes with major trading partners such as China and Mexico. Another 26 per cent cited rising healthcare costs, while just 7 per cent pointed to the Fed’s interest rate policies. Last week, the Fed cut interest rates by 25 basis points for the third time this year.

With Mr Trump recently deploying US troops to Saudi Arabia and oilfields in northern Syria, the poll found that 55 per cent of Americans feel petrol prices should be an important factor in US military decision making in the region. Nearly three-quarters said higher petrol prices would have a negative impact on their personal finances.

The FT-Peterson poll was conducted online by Global Strategy Group, a Democratic polling firm, and North Star Opinion Research, a Republican group, between October 21 and October 25. It reflects the opinions of 1,005 likely voters nationwide, and has a margin of error of plus or minus 3 percentage points.

The Peterson Foundation is a non-partisan, non-profit organisation focused on America’s fiscal challenges.

“The FT-Peterson poll is part of the FT’s expanding coverage of US economic and financial issues heading into next year’s presidential election,” said Peter Spiegel, the FT’s US managing editor. “We want it to be the single point of reference for how Americans now answer that question Ronald Reagan made famous in 1980: ‘Are you better off than you were four years ago?’”