An increasing number of Americans are losing confidence in the economy, according to a new Quinnipiac University poll, which spells trouble for President Donald Trump's re-election campaign.

The poll found 37 percent of Americans say the economy is getting worse, 31 percent say it's getting better, and 30 percent say it's staying the same.

This is the first time in over two years and the first time since Trump was elected that more Americans say the economy is getting worse than better.

"As trade tensions with China dominate the headlines, confidence in the economy is slipping," Quinnipiac University polling analyst Mary Snow said in a statement on the poll's findings.

Trump's campaign pitch is that he's been great for the economy. A lot of Americans are apparently unconvinced. And if a recession hits, his case for staying in office falls apart.

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Americans are losing confidence in the economy — and that's terrible news for President Donald Trump as he heads into an election year.

For the first time in over two years — and the first time since Trump was elected — more Americans say the economy is getting worse than better, according to a new Quinnipiac University poll.

The poll found 37 percent of Americans say the economy it is getting worse, 31 percent say it's getting better, and 30 percent say it's staying the same. The poll also found an increasing number of Americans disapprove of Trump's handling of the economy, with 46 percent approving and 49 percent disapproving. Comparatively, a Quinnipiac poll from May found 48 percent approving of Trump's handling of the economy and 45 percent disapproving.

Even as many Americans lose confidence in the economy and think Trump is hurting it, 61 percent still stay it's in excellent or good shape while 37 percent say that it is not so good or poor.

'As trade tensions with China dominate the headlines, confidence in the economy is slipping'

Trump's trade war with China has escalated dramatically in recent weeks, prompting fears of an economic recession among economists and financial experts.

The yield curve inverted earlier this month (interest rates on long-term Treasury bonds fell below rates on short-term bonds), prompting panic among investors. Every recession in the US since the 1960s was preceded by a yield curve inversion, though it doesn't necessarily indicate an economic downturn is inevitable.

The Federal Reserve also lowered interest rates for the first time in over a decade in late July, which can also be interpreted as a sign of faltering confidence in the economy. There are positive numbers swirling around the US economy, such as historically low unemployment, but the chaos surrounding global trade is not helping matters.

The president, however, has pushed against the notion an economic downturn is on the horizon, and defended his controversial trade tactics.

But the new Quinnipiac poll found a significant portion of voters (41%) say Trump's policies are hurting the economy, while 37 percent say that they are helping, and 20 percent say that his policies make no difference.

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"As trade tensions with China dominate the headlines, confidence in the economy is slipping," Quinnipiac University polling analyst Mary Snow said in a statement on the poll's findings. "The number of people who think the economy is getting worse rose by double digits since June. And roughly 4 in 10 voters blame the President's policies, saying they are hurting the economy, the highest level since Trump took office."

The poll also found all five of the top 2020 Democratic presidential candidates beating Trump if the election were held today, with former Vice President Joe Biden dominating overall (54 percent would vote for Biden while just 38 percent would vote for Trump).

Voters also give Trump a low approval rating (38 percent), with 56 percent disapproving of his handling of the presidency.

Trump's campaign pitch is that he's been good for the economy, but a lot of Americans are unconvinced.

The economy has generally been in good shape throughout Trump's tenure thus far and polling has frequently showed voters approving of the president's handling of it even if they disapproved of his approach to the presidency more broadly.

And even with a low approval rating, Trump could win in 2020. He won the 2016 election with just 46% of the popular vote.

But if confidence in the economy continues to slip it could see Trump's numbers dip to a place where he'd have a far more difficult time winning re-election.

Trump's central campaign pitch is that he's been good for the economy. At a campaign rally in New Hampshire earlier this month, Trump told supporters they have "no choice" but to vote for him or the economy would "go down the tubes."

"If for some reason I wouldn't have won these elections, these markets would have crashed. And that'll happen even more so in 2020," Trump said.

Based on this Quinnipiac poll, Trump is struggling to convince a large cohort of voters that this is the case. And if a recession hits, it completely undermines Trump's case for staying in office.

Other recent data from The Conference Board's Present Situation Index shows Americans' view of the economy is the most favorable it's been in 19 years. With that said, Trump's trade war with China threatens to undermine that confidence.

"While other parts of the economy may show some weakening, consumers have remained confident and willing to spend," Lynn Franco, the senior director of economic indicators at The Conference Board, said in a statement.

"However, if the recent escalation in trade and tariff tensions persists, it could potentially dampen consumers' optimism regarding the short-term economic outlook," Franco added.