From new CNN poll:

Back in April, Americans who dislike both parties appeared to mildly favor the GOP on the generic ballot, by a 43-to-39 percent margin, with a large number saying at the time that they would pick a minor-party candidate or stay at home.

“Now, a lot of those voters appear to be bolting to the GOP,” Holland said. “Republicans now have a whopping 38-point advantage on the generic ballot among voters who dislike both parties.”

Republicans also have a large and growing advantage among independents. Sixty-two percent of independents questioned say they would vote for the generic Republican in their district, with three in 10 saying they’d cast a ballot for the generic Democrat. That 32-point margin for the Republicans among independents is up from an 8-point advantage last month.

“It’s not surprising that those two groups are voting the same way, since almost by definition independents don’t like either party,” says Holland.