They're pointing fingers at FBI Director James Comey, unfair media coverage and voters resistant to electing the first woman president.
But many Democrats believe the list should begin with this: Clinton and her campaign.
As a new political order falls over Washington, advisers close to Clinton are trying to get ahead of a bitter round of finger-pointing inside a newly-decimated Democratic Party. In a conference call with top donors Friday, campaign chairman John Podesta said a "hostile press corps" contributed to Clinton's defeat. Other top advisers said Comey's decision to take another look at Clinton's emails stopped the campaign's momentum and motivated Trump voters. That bombshell contributed to a significant fall-off among college educated voters "who fizzled at the end," an adviser said. Those voters, always wavering about Clinton, were simply turned off at the end.
The call on Friday, which was described to CNN by several participants, did not specifically address one of the biggest questions many Democrats have: How did Clinton allow Wisconsin, Michigan and Pennsylvania to fall away from the party?
Clinton is expected to hold a conference call of her own later Friday with donors and other supporters, CNN has learned, to offer her first explanation of the crushing defeat.
The campaign communications director, Jennifer Palmieri, said in a statement Friday that "no one anticipated" losing. She said many factors were at work, but she listed Comey as chief among them.
"We didn't blame everyone but ourselves," Palmieri said. "We acknowledged a lot of challenges we faced, plenty of mistakes made along the way, some challenges we weren't able to overcome."
She added: "What changed in the last week that made his turn out go up and our's go down? The only thing apparent was Comey. It was one thing too many. Could not overcome it."
Democrats close to Bill Clinton said Thursday that one mistake Clinton's top aides made was not listening to the former president more when he urged the campaign to spend more time focusing on disaffected white, working class voters.
Many in Clinton's campaign viewed these voters as Trump's base, people so committed to the Republican nominee that no amount of visits or messaging could sway them. Clinton made no visits to Wisconsin as the Democratic nominee, and only pushed a late charge in Michigan once internal polling showed the race tightening.
Bill Clinton, advisers said, pushed the campaign early on to focus on these voters, many of whom helped elected him twice to the White House. The former president, a Clinton aide said, would regularly call Robby Mook to talk about strategy and offer advice.
But aides said the Clinton campaign's top strategists largely ignored the former president, instead focusing on consolidating the base of voters that helped elect President Barack Obama to the White House. In the closing days of the campaign, Clinton targeted young people, Hispanics and African-Americans with laser like focus, casting Trump as a racist who only sought the presidency to benefit himself.
As Tuesday night's results rolled in, those voters seemingly didn't do enough to propel Clinton past the wall of white, working class people who backed Trump. Clinton's internal polling was also off. Days before the election, Clinton's internal polling showed Clinton up by four points in Michigan, according to an aide.
"It's is nothing short of malpractice that her campaign didn't look at the electoral college and put substantial resources in states like Michigan and Wisconsin," Democratic pollster Paul Maslin told the Milwaukee Journal Sentinel.
Neither Clinton nor Obama visited Wisconsin once during the general election campaign. The state voted Republican for the first time in a presidential race since 1984.
Wisconsin is emerging as one case study for where the Clinton campaign fell short. She won voters under 30 by just 4 points, according to exit polls, while Obama won them by 23 points four years ago.
An aide said Friday that the campaign's top staffers understood they couldn't "recreate the Obama coalition" exactly, but deeply felt that "college educated whites would be part of a new coalition for her."
"In the end, that did not materialize in big enough numbers in Michigan, Wisconsin and Pennsylvania," the aide said.
Another aide pointed to Pennsylvania -- a state Clinton visited 11 times after the Democratic National Convention in Philadelphia -- as proof that more visits would not have helped.
Asked if there was anything they could have done in states like Michigan and Wisconsin to beat Trump, a top aide offered: "Not had Comey send his letter."