Poll: Trump third-party run would hurt Bush
© Greg Nash

If Donald TrumpDonald John TrumpReporters defend CNN's Acosta after White House says he 'disrespected' Trump with question Security costs of Trump visit to Scotland sparks outrage among Scottish citizens Ex-CIA officer: Prosecution of Russians indicted for DNC hack 'ain't ever going to happen' MORE leaves the GOP and runs as an independent candidate for president, it would badly damage Republican prospects for winning the White House, a new poll finds.

An ABC News-Washington Post poll released late Monday showed that in a head-to-head matchup, former secretary of State Hillary ClintonHillary Diane Rodham ClintonDHS secretary: No sign Russia targeting midterm elections at 2016 level Twitter suspends Guccifer 2.0 and DCLeaks accounts after indictments Elon Musk donated nearly K to Republican PAC, filings show MORE (D) has a small lead over former Florida Gov. Jeb Bush (R) at 50 percent to 44 percent.

However, in a three-way matchup between Clinton, Bush and Trump, Trump siphons off significant support from Bush, propelling Clinton to a 16-point lead.

In that scenario, Clinton takes 46 percent over Bush at 30 percent and Trump at 20 percent. Bush was the only Republican contender the poll tested in a three-way match up with Clinton and Trump.

“The results underscore the GOP’s conundrum in responding to Trump, a billionaire businessman and television celebrity who hasn’t ruled out an independent run for the presidency,” Gary Langer, who conducted the poll, wrote in a memo.

Trump has said that his plan is to win the Republican nomination for president, but he has repeatedly declined to rule out an independent bid. Trump’s fortune is in the billions, and he’s already self-funding his current run for the GOP nomination.

Trump is riding a media frenzy to the top of the polls. This week, he moved into the lead of the RealClearPolitics average of polls, with the last three national surveys finding him in first place.

The ABC News-Washington Post survey showed Trump with a big lead over the field. He takes 24 percent support in the poll, with Wisconsin Gov. Scott Walker a distant second at 13 percent, followed by Bush at 12 percent.

Still, many believe the early polls are driven by name recognition and that Trump’s support will dissipate. The ABC News-Washington Post poll found that a majority of Republicans say Trump does not represent the GOP’s core values, and 30 percent of Republicans said they’d never even consider voting for him.

Trump's recent controversial comments criticizing Sen. John McCain's (R-Ariz.) war record could cost him, however. The poll found a significant slide in support for Trump after his remarks on Saturday.

The ABC News-Washington Post poll of 1,002 adults was conducted between July 16 and July 19 and has a 3.5 percentage point margin of error.