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As President Trump heads to Florida for the official launch of his 2020 campaign, a new poll shows him trailing several of his potential Democratic opponents in the key state.

Former Vice President Joe Biden leads Trump by 9 points among Florida voters in a survey released by Quinnipiac on Tuesday, with Biden scoring 50 percent to Trump's 41 percent. Sen. Bernie Sanders (I-Vt.) also leads Trump by six points, and Sen. Elizabeth Warren (D-Mass.) leads him by four points.

Several other potential Democratic contenders were within the margin of error of Trump, with Sen. Kamala Harris (D-Calif.), former Rep. Beto O'Rourke, and South Bend Mayor Pete Buttigieg beating Trump by one percentage point. During the 2016 election, Trump carried Florida by a slim margin of just over one percent.

In this poll, 44 percent of Florida voters said they approve of the way Trump is handling his job as president, with 51 percent disapproving. It's not all bad news for the president, though, as 62 percent of Florida voters said Congress shouldn't begin impeachment proceedings against him, and 54 percent of voters said they're better off financially today than they were in 2016.

This comes after Trump fired three pollsters following reports of poor internal polling, including one reportedly showing Biden beating Trump by seven points in Florida. Biden during an event on Monday predicted he will beat Trump in Florida, also saying he hopes to compete in traditionally-red states like Texas and South Carolina. Still, he cautioned at an event on Tuesday per CNN that "I don't believe the polls right now, guys."

Quinnipiac's poll was conducted from June 12 through June 17 by speaking to 1,279 Florida voters over the phone. The margin of error is 3.3 percentage points. Read the full results at Quinnipiac.