A new survey finds that most Americans think that President Biden “helped and participated in” the business affairs of his troubled son, Hunter. The poll’s findings come as House Republicans are subpoenaing the first son and his uncle, James Biden, as they pursue an impeachment inquiry into the president.

A new Harvard Harris survey found that 60 percent of Americans report thinking that the president “helped and participated in” Hunter Biden’s business.

Broken down by partisanship, 39 percent of Democrats believe the president participated in his son’s business dealings, and 81 percent of Republicans and 59 percent of independents said the same.

Yet 61 percent of Democrats, 19 percent of Republicans, and 41 percent of independents reported thinking that the president did not participate in his son’s business dealings.

The survey comes ahead of the House GOP’s plans to depose the president’s son, whom Republicans have subpoenaed, in December. Congressman James Comer, who is leading the impeachment inquiry, claimed on Friday that the White House is not cooperating with the subpoenas.

The thrust of the impeachment effort is the allegation, leveled by Republicans, that the president improperly used his office during his time as vice president in order to further his son’s business interests.

Yet House Republicans have not yet provided clear evidence that the president acted in a way worthy of impeachment, something even some of Mr. Biden’s harshest antagonists, such as  Congressman Jim Jordan, have acknowledged.

“We get those depositions done this year and … then we can decide on whether or not there’s articles,” Mr. Jordan told Politico.

While Republicans are planning to depose the president’s brother and son, they are not expected to hold another hearing, a decision made after the first and only impeachment hearing in September, when the Republicans’ own witnesses said they did not see evidence of impeachable conduct.

The Harvard Harris survey suggests that House Republicans have already accomplished one goal of the impeachment: embroiling Mr. Biden in a public scandal involving his family.

The survey also found that another principal Republican criticism of Mr. Biden had also gained traction among the public, with 51 percent of respondents reporting thinking that the president is too old to run an effective campaign, while 49 percent believe he “can run an effective campaign.”

Broken down by partisanship, 78 percent of Democrats, 26 percent of Republicans, and 41 percent of independents think Mr. Biden could run a campaign. On the other hand, 22 percent of Democrats, 74 percent of Republicans, and 59 percent of independents reported thinking that Mr. Biden would be unable to run an effective campaign.