Washington (CNN) A majority of Americans say they think Congress opening an impeachment inquiry into President Donald Trump is necessary, according to a CBS News poll released Sunday.

The poll , conducted by YouGov, shows 55% of Americans think the newly-opened probe necessary, while 45% of Americans think it unnecessary.

On Tuesday, House Speaker Nancy Pelosi announced a formal impeachment inquiry into the President after a transcript of a July call with Ukranian President Volodymyr Zelensky revealed he pushed Zelensky to investigate former Vice President Joe Biden -- his potential 2020 political rival -- and his son, Hunter. There has been no evidence of wrongdoing by either Joe or Hunter Biden.

A separate whistleblower complaint also alleges Trump abused his official powers "to solicit interference" from Ukraine in the upcoming 2020 election, and that the White House took steps to cover it up. Trump has denied doing anything improper.

Among Democrats, nearly 9 in 10 approve of the inquiry and two-thirds strongly approve -- 87% of Democrats approve of the inquiry, according to the poll. Meanwhile, 77% of Republicans disapprove and 23% approve starting an impeachment inquiry. Among Independents, 49% approve and 51% disapprove, the poll found.

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