A new national poll by Quinnipiac University indicates that 55 percent of registered voters support the House Democrats' impeachment investigation into President Trump, with 43 percent opposed.

Support for impeachment is up 4 percentage points from a Quinnipiac poll a week ago, when the split stood at 51-45 percent, and marks a new high in the survey.

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The survey also indicates that by a slight 48-46 percent plurality, registered voters say the president should be impeached by the House and removed from office through a trial in the Senate. In Quinnipiac’s poll from a week ago, support for impeachment and removal from office was slightly underwater, at 46-48 percent.

The poll spotlights the wide partisan divide over impeachment, with Democrats approving of the inquiry by a 93-7 percent margin and Republicans disapproving 88-10 percent. A majority of independents back the inquiry by a 58-37 percent margin, with support rising 8 points in a week.

The president has come under fire over his July 25 call with Ukrainian President Volodymyr Zelensky, in which he urged Zelensky to investigate former Vice President Joe Biden and his son Hunter over their dealings in the eastern European country that’s been battling Russia. Biden is one of the top Democratic 2020 presidential contenders hoping to challenge Trump in next year’s election. Fueled by whistleblower complaints and a transcript of the call released by the White House, Democrats argue the president was asking a foreign country to potentially interfere in a U.S. election.

Adding to the controversy was the fact that before that phone call, millions in U.S. military aid to Ukraine was put on hold. Despite allegations that Trump was using that money as leverage, Trump has repeatedly insisted that he did nothing wrong. He says there was no "quid pro quo" and has on numerous occasions described his conversation with the Ukrainian leader as “perfect.”

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The president and allies have repeatedly tried to put the spotlight in the scandal on the Bidens. Hunter Biden served on the board of a Ukrainian energy company while his father was vice president. Trump and fellow Republicans have questioned how Biden pushed in 2016 for the dismissal of a Ukrainian prosecutor who was looking into corruption at the company. The prosecutor – who had been widely accused by both Democrats and Republicans of overlooking corruption in his own office – was later dismissed.

Biden, defending his actions in Ukraine, has said "there’s no truth to [Trump's] charges and attacks against me and my son. Zero."

Acting U.S. Ambassador to Ukraine Bill Taylor testified on Tuesday that the president pushed Ukraine to investigate both interference in the 2016 presidential election and the company linked to Hunter Biden — and was willing to hold up military aid and a White House meeting to get a public announcement from the country that the probes were underway.

Fifty-nine percent of those questioned in the new poll say the president was pursuing his own personal interests in his dealings with Ukraine, with a third saying Trump was pursuing the national interest.

“Republicans remain rock solid in opposing both the impeachment of President Trump and the House impeachment inquiry. But when it comes to the president’s motives in Ukraine, Republicans aren’t all on the same page. Roughly 7 in 10 Republicans say the president was pursuing the national interest in his dealings with Ukraine. The rest say he was pursuing his own personal interest or they don’t know,” Quinnipiac University Polling Analyst Mary Snow said in a statement.

The Quinnipiac University poll was conducted Oct. 17-21, with 1,587 self-identified registered voters questioned by live telephone operators. The survey’s overall margin of error is plus or minus 3.1 percentage points.

RECORD SUPPORT FOR IMPEACHMENT IN FOX NEWS POLL

The release of the poll comes two weeks after a national Fox News Poll indicated 51 percent support for impeaching and removing Trump from office, with 40 percent opposed.