Story highlights

A new Fox News poll shows Trump on top

It also shows support for Bush eroding

CNN  — 

A trio of Republican establishment favorites – Jeb Bush, Scott Walker and Marco Rubio – are all losing ground in the party’s 2016 presidential field, a new Fox News poll shows.

Donald Trump, meanwhile, continues to dominate the race, earning 25% support nationally, while another outsider, retired neurosurgeon Ben Carson, is running second at 12%. Sen. Ted Cruz of Texas, known for locking horns with Republican congressional leaders, is third at 10%.

Bush, the former Florida governor, has dropped to 9% – fourth place, down from 15% and second place in a Fox News poll conducted earlier this month, before the first GOP presidential debate.

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Walker, the Wisconsin governor, meanwhile, is tied for fifth, at 6% – down from 9% earlier this month. And Rubio, the senator from Florida, is now at 4% – in ninth place, and down from 5%.

The results, with outsiders at the front of the field and establishment favorites struggling to gain traction, reflect a shift among likely Republican primary voters toward candidates who challenge the political hierarchy.

In the new Fox News poll, former Arkansas Gov. Mike Huckabee tied with Walker for fifth at 6%. They’re followed by former Hewlett Packard CEO Carly Fiorina at 5%, Ohio Gov. John Kasich at 4%, Rubio, and then New Jersey Gov. Chris Christie and Sen. Rand Paul of Kentucky, who are both at 3% support.

The poll was conducted Aug. 11-13. It has a margin of error of plus or minus 3 percentage points.

CORRECTION: This story has been updated to reflect that the poll’s margin of error is 3 percentage points