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Donald Trump edges ahead of Jeb Bush in Florida

Joe Biden runs as well or better than Hillary Clinton against Republicans in three swing states

(CNN) —  

Donald Trump’s feud with Jeb Bush just got more interesting as the billionaire businessman is now leading the former governor in his own state of Florida, a general election battleground that carries increasing importance in the GOP primary race, according to a new poll.

Trump is leading the GOP presidential primary race in Florida with 21% of support compared to Bush’s 17%, according to a Quinnipiac University poll released Thursday. Florida Sen. Marco Rubio also trails both Trump and Bush, tying retired neurosurgeon Ben Carson with 11% among registered Republican voters.

The Quinnipiac survey also shows Vice President Joe Biden, who is still mulling a presidential run, is running equal to or better than Hillary Clinton against the top Republican contenders in Florida, Ohio and Pennsylvania, three key general election swing states.

Biden came out ahead of Trump, the Republican front-runner, by 3 points in Florida, 10 points in Ohio and 8 points in Pennsylvania.

RELATED: Town hall throw-down: Trump, Bush trade shots

Clinton, by contrast, trails Trump by two points in Florida and leads the businessman by 5 points in Ohio and 5 points in Pennsylvania, according to the poll.

Despite their front-runner status, Trump and Clinton top the list of candidates with the worst favorability ratings in the three swing states. They are also perceived as the least honest and trustworthy of all the candidates in those states; more than half of voters in the three states have a negative view of Clinton and Trump.

In Pennsylvania, Trump came out ahead of the rest of the GOP field, registering 24% of support – double digits ahead of his closest competitors Bush and Rubio who notched 13% and 10%, respectively, according to the Quinnipiac poll.

Ohio Gov. John Kasich retained his home state advantage with 27% of support, according to the poll, but Trump trails closely behind with 21%.