Hillary Clinton is settling old scores in a campaign tell-all book - and angering some Democrats in the process.

Excerpts from "What Happened," the Clinton campaign memoir scheduled to be released next week, find her letting loose on the Democratic Party's most popular figures and venting frustration with a process that culminated in her shocking election defeat by Donald Trump.

In the book, Clinton says she was put in a "straightjacket" during the primary by former President Obama, who she writes advised her not to attack Sen. Bernie Sanders (I-Vt.), her rival in the Democratic primary, out of fear it would divide the party ahead of the general election.

Clinton writes that she bristled at former Vice President Joe Biden's suggestion that she failed to adequately convey the Democratic Party's commitment to helping the middle class.

And Clinton unloads on Sanders, mocking his policy proposals as pie-in-the-sky fantasies and ripping his supporters on social media - the so-called Bernie bros - as sexist.

Clinton says that Sanders's attacks did "lasting damage" to her general election hopes. She accuses him of "paving the way" for Trump to cast her as a corrupt corporate stooge deserving of the nickname "Crooked Hillary."

Sanders brushed off Clinton's criticism in a Wednesday interview with The Hill, saying it's time for Democrats to "look forward, not backward."

Not everyone was so charitable. Even some of Clinton's allies have grown weary of her insistence on re-litigating the 2016 campaign at a time when the Democratic Party is looking to forge a new identity in the age of Trump.

"The best thing she could do is disappear," said one former Clinton fundraiser and surrogate who played an active role at the convention. "She's doing harm to all of us because of her own selfishness. Honestly, I wish she'd just shut the f--- up and go away."

Since her loss, Clinton has taken fire from both sides of the aisle for what's seen as her refusal to acknowledge her own role in her campaign's defeat.

She has blamed Russian hackers, sexism and former FBI Director James Comey for her defeat. But she has proven less vocal about flaws in her own campaign.

Clinton's latest election musings have also reopened old wounds from the bitter primary fight with Sanders right as Democrats say their focus should be on finding an economic message that appeals to the Rust Belt voters who abandoned the party for Trump.

There is an urgency to unite the progressive and mainstream wings of the party ahead of the 2018 midterm elections, when Democrats will face a brutal slate of Senate reelection campaigns in states that Trump carried over Clinton.

Those daunting challenges have some Democrats fuming at what they view as Clinton's petty post-election score settling.

"None of this is good for the party," said one former Obama aide. "It's the Hillary Show, 100 percent. A lot of us are scratching our heads and wondering what she's trying to do. It's certainly not helpful."

Sanders backers are apoplectic.

The book threatens to once again anger Sanders's energetic base, many of whom have already been alienated from the Democratic Party after emails released by Russian-backed hackers showed Democratic National Committee staffers opposed Sanders's bid during the primary. Since the election, Sanders's supporters and most prominent surrogates have frequently clashed with what they see as members of a Clinton-tied old guard over the party's direction in the Trump era.

"Democrats, and all voters, can take a look at the two different visions, ably articulated, by the two Democratic finalists," said progressive activist and writer Jonathan Tasini.

"One person has been out in the country, almost without stopping, since the election rallying people to defend ObamaCare, against tax cuts for the wealthy and for a $15 minimum wage. The other person, while Trump has been ripping the country apart, has been taking long walks in the woods, drinking chardonnay, hobnobbing with celebrities and writing a book that entirely ignores the failure of the party establishment over a decade or two. People can choose which kind of party they prefer."

Still, Clinton enjoys widespread goodwill in Democratic circles.

"She still has matriarchal capability, because she was the first lady of Arkansas, the first lady of the country, a United States senator and secretary of State," said Rep. John Larson (D-Conn.). "Hard to find any elected Democratic woman who has had her status and over such a long period of time."

Most Democrats reached by The Hill did not want to speak ill of Clinton, feeling sympathy for her loss and believing that she's still trying to come to grips with it.

"This was a heartfelt loss for her and the pain is unimaginable, and I'm sure this book was cathartic," said Democratic strategist Steve McMahon.

And many Democrats agree with Clinton's reading of the election, even if they're tired of rehashing it.

"I said in the very beginning of the primary that Bernie Sanders, which he had every right to do, but his run was going to divide us more than unite us," said Rep. Bill Pascrell (D-N.J.). "And I think I was proven correct. I think she was right substantially about Bernie, but it's done."

Those who experienced the wrath of the "Bernie bros" over social media maintain that there were sexist elements to their criticisms, even if the attacks were not sanctioned by the candidate himself.

Whether Sanders carried his campaign on long after the outcome was a foregone conclusion, further damaging the eventual nominee, will be one of the enduring debates from the 2016 election.

But there is widespread eagerness among Democrats to see Clinton channel her status in the party into something more meaningful than pursuing old campaign grudges.

"She's brilliant and has a lot to offer on foreign policy, on economic issues, on governing," said Texas Democratic Chairman Gilberto Hinojosa. "I think what people want from her, and what the party needs, is the guidance she can provide in how we proceed in the future. She has a lot to offer in that respect, even if she didn't reach everyone she needed to in the campaign. But she needs to not worry about what happened in the past."

Democrats say the real lesson from 2016 is that the party needs a stronger economic message, a blind spot they say left them vulnerable to Trump. They believe anything that distracts from that goal is counterproductive.

"The morning after the election I wrote on Facebook that we needed to all own our part and focus on the road ahead," said Democratic strategist Steve Schale, who attempted to draft Biden into the 2016 race. "I still believe this, and the sooner we stop talking about 2016, all of us on my side, and get to work on the real organizing required for 2018, the better off we will be not only in the midterm elections, but also in 2020."

Mike Lillis, Amie Parnes and Alexander Bolton contributed.