One-third of Republicans worry that US President Donald Trump's family business has influenced his decisions in the White House, according to a new poll released on Tuesday.

Iran PressAmerica: The national online poll, conducted on Monday and Tuesday, followed a New York Times investigation that found Trump, a self-described billionaire, is deeply in debt and has regularly paid little to nothing in federal income taxes over much of the past two decades.

The poll found that three in 10 Republicans were concerned that Trump’s personal finances have influenced his decisions as president, and two out of 10 Republicans said they do not think Trump has paid his "fair share" of income taxes.

Nearly three in 10 Republicans also have said they believed the recent Times report.

Among all likely voters, a separate Reuters/Ipsos polling showed Biden with a 9 percentage point advantage nationally, which is unchanged from the previous week.

Fifty-one percent said they backed Biden while 42% said they would vote for Trump. The remainder are undecided ahead of the Nov. 3 election.

The picture is much different outside of the Republican Party, however.

The poll on Trump’s taxes found that 51% of American adults said they believe that Trump has not been paying his "fair share" of income taxes.

And 56% of all Americans said they are "very" or "somewhat" concerned that Trump’s decisions as president were influenced by his personal interest in making money.

The responses were somewhat split along party lines. Nine out of 10 Democrats said they felt Trump was not fairly paying his share of taxes, compared with about six out of 10 Republicans who felt that Trump was paying the right amount.

Among independents, four out of 10 said Trump was not paying his fair share, while two out of 10 said that he was.

The Reuters/Ipsos poll was conducted online, in English, throughout the United States. The Sept. 28-29 poll gathered responses from 1,005 American adults, while the Sept. 25-29 poll surveyed 864 likely voters. The surveys have a credibility interval, a measure of precision, of 4 percentage points.