A new poll released by Fox News holds some surprises for both parties.  On the rise in the new survey are Ben Carson, Carly Fiorina, and Ted Cruz.  Falling are Jeb Bush, Scott Walker, and Rand Paul.

Businessman Donald Trump still leads the field for the Republican nomination. He gets 25 percent among GOP primary voters. He was at 26 percent before the debate. Trump’s support among women went from 24 percent two weeks ago to 21 percent now. He mostly held steady among men (28 percent).

The real-estate mogul maintains his first-place status despite also being judged in the poll as having the worst debate performance and being considered the least likeable Republican candidate. More on that later.

The August 6 Republican presidential debate was hosted by Fox News Channel in Cleveland. Several of the exchanges at the debate remained in the news for days after.

Next in the GOP race is Carson, who garners 12 percent. That’s up five percentage points since the debate and puts him in double-digits for the first time since mid-June. Cruz captures 10 percent, up four points.

Bush has dropped to nine percent. That’s down six points — and puts him in single digits for the first time since April. That’s likely a result of his debate performance, which was judged subpar by those who watched. Bush does well on other measures — he’s seen as both likeable and qualified.

Former Arkansas Gov. Mike Huckabee held steady at six percent. Walker slips to six percent — down three points and the lowest support he’s received for more than a year.

Fiorina garners five percent support (+3 points), with Kasich (+1) and Rubio (-1) both at four percent. New Jersey Gov. Chris Christie and Paul each get three percent. The remaining candidates are at one percent or less.

[...]

On the Democratic side, Clinton drops below 50 percent for the first time, while Sanders keeps climbing. She leads among Democratic primary voters by 19 points (49-30 percent). Two weeks ago Clinton was up by 29 points (51-22 percent). A month ago she had a 40-point advantage (59-19 percent).

Vice President Joe Biden, who is undeclared, receives the backing of 10 percent.

The remaining Democratic candidates are at one percent or less.

WaPo's Chris Cillizza thinks it's too late for Democrats to "rethink Hillary's viability":

Dear Democrats: It’s too late to start over.

As in, there’s no replacing Hillary Rodham Clinton as your party’s front-runner for the presidential nomination. Not with Vice President Biden — even if he runs. Not with former vice president Al Gore. (I mean, come on.) Not with your ideal rich-person-with-no-record-and-a-fresh-faced-appeal.

This may come as a shock to some of you. After all, you argue, it’s only August! The Iowa caucuses won’t be until February! That’s, like, four political lifetimes.

Sure. But modern presidential politics isn’t as simple as announcing that you’ve decided to run and watching yourself soar to the top of the polls. (Unless, of course, you are Donald Trump, who appears entirely immune to every political law of gravity.)

Bernie Sanders may be drawing enthusiastic crowds, but the professional politicos in the Democratic Party know he can't win a national election.  As a symbol of dissatisfaction and anger, he does very well.  But as a flesh-and-blood candidate – like Donald Trump – there is a ceiling to his support well short of 50%.

Carson's rise is the most interesting part of this poll, given he was a little lost in the shuffle during the debate.  He didn't get enough face time, but what he got apparently impressed a lot of voters.

Fiorina has now vaulted into the bottom of the first tier of candidates, as has John Kasich, who will get an eye-opening endorsement today from the governor of Alabama, Robert Bentley.  Both of those candidates have the ability to sneak up on the frontrunners if they can raise enough cash to be competitive.