Democrats, reveling in President Donald Trump’s plummeting popularity and the Republican Party’s civil wars, are looking forward to September. Except for one thing: the rollout of Hillary Clinton’s next book right after Labor Day.

Clinton has promised to “let my guard down” in the book, “What Happened,” explaining her shocking loss to Trump in November. She has already offered up several explanations, blaming Russian interference, former FBI Director James Comey, and misogyny, while also acknowledging tactical errors by her campaign.

Many Washington Democrats, though unwilling to criticize her in public, wish she’d “move on,” as Minnesota Sen. Al Franken has put it. They fear that her complaints help Trump make his case that the controversies surrounding him flow from the Democrats’ bitterness about their 2016 loss.

They prefer the approach taken by Al Gore after his equally controversial loss in 2000. Gore didn’t really criticize the administration of President George W. Bush for almost two years even though he, like Clinton, won the popular vote while losing in the Electoral College. (Gore lost when the Supreme Court stopped a vote recount in Florida.) Gore went on to start a new career, winning a Nobel Prize and an Academy Award for his work on climate change.

Associates hoped Clinton would also find a way to make a different contribution, perhaps as a university president or foundation head. There have even been suggestions that she move overseas for a couple of years.

Clinton could make a contribution speaking out selectively on important issues, drawing on her wealth of experience.

But she remains haunted by her defeat. The gist of her message next month, based on her public statements and accounts of private conversations from people who’ve talked to her, will be: I accept the blame for what happened, but the bigger problems were Russian meddling, Comey’s on-again, off-again handling of the FBI’s probe of her private email server, the Democratic Party, and maybe even some of her own campaign staffers.

The Clintons, associates say, are convinced that the election was stolen. They may be right; we’ll find out soon enough whether there’s proof that the Trump campaign colluded with Russia. If investigations by congressional committees and special counsel Robert Mueller turn up new facts, that’ll provide a better basis for analyzing the impact.

But Clinton is the wrong messenger. She just comes across as a sore loser.

Or as Senate Minority Leader Charles Schumer told The Washington Post last month: “When you lose to somebody who has 40 percent popularity, you don’t blame other things — Comey, Russia — you blame yourself.”

She could take a lesson from another prominent Democrat, one who has kept a relatively low profile since January. That’s former President Barack Obama, who has mostly resisted the temptation to strike back at repeated Trump cheap shots. Today, surveys of voters have found, he’s the most popular American politician. Some Democrats want him to take on Trump a bit more, and are pleased he’ll be out campaigning for a few Democrats this fall.

By contrast, Clinton has moved from being an admired former New York senator and secretary of state to becoming a divisive and unpopular figure. In last month’s Bloomberg national poll, 58 percent of respondents rated her unfavorably compared to 39 percent who gave her favorable marks. More than one in five people who voted for her in November now regard her unfavorably. That was even worse than Trump’s standing in the same poll.

Indeed, the only figure with higher negatives in the survey, which was conducted by the Iowa polling firm Selzer & Co., was her old nemesis, Russian President Vladimir Putin.

E-mail Albert R. Hunt at ahunt1@bloomberg.net. Follow him on Twitter: @AlHuntDC

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