A new national poll shows that former Vice President Joe Biden has opened up a 15-point lead over President Donald Trump. The poll also raises bad news for the President on the economy, his most important selling point for reelection.

Iran PressAmerica: A majority of registered voters (52%) report they'll support Biden in the general election, with 37% going for Trump, a wider margin than in Quinnipiac's June poll when 49% backed Biden and 41% supported Trump, according to CNN.

The poll also finds growing disapproval of Trump's job performance -- with a notable shift on the economy where reviews of Trump's performance have turned negative. The economy had been the only issue on which Trump earned a net positive rating in Quinnipiac's polling, but now, 44% approve while 53% disapprove of his performance.

Overall, the survey finds 36% of registered voters approve of the way Trump is handling his job generally, and 60% disapprove, compared with 42% approve to 55% disapprove in June.

The survey also finds Biden edging out Trump when voters are asked who would do a better job handling the economy -- 50% say Biden and 45% for Trump, a reversal from June when 51% said Trump would do a better job, 46% Biden.

Biden also holds broad advantages over Trump on who would do a better job addressing racial inequality (+32 points for Biden), handling the response to the coronavirus (+24 for Biden), health care (+23 for Biden), and handling a crisis (+19 for Biden).

Most registered voters (61%) disapprove of the way Trump is handling the reopening of schools, while only 29% approve. Trump's approval on this issue is about the same among parents of kids under the age of 18 (30%).

The Quinnipiac poll shows a majority of voters (62%) think it will be unsafe to send students to elementary, middle and high schools in the fall, 31% believe it will be safe. In May, 40% felt it would be safe to send students back to school. Around the same number (34%) thought it would be safe to send college students back in the fall.

A separate state poll also gave Trump some bad news in a key state.

A Pennsylvania poll from Monmouth University, also out Wednesday, finds Biden leading Trump significantly -- Biden with 53% of registered voters, 40% for Trump.

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