Hillary Clinton isn't running, but she hasn't gone away (even if some might like her to)

DES MOINES, Iowa — It can't be fun for Hillary Clinton to be watching the 2020 election play out.

One of her former foes, Bernie Sanders, is surging in Iowa ahead of Monday's caucuses, while her other foe, Donald Trump, is now president and held a massive rally here Thursday night to promote his juggernaut re-election campaign.

A third old political rival, former President Barack Obama, who beat Clinton in 2008 Democratic primary starting Iowa, is praised and revered almost daily in ads and speeches from the Democratic presidential candidates.

Her name is rarely mentioned and when her name does come up, it's often not in a good way.

But Clinton has still made her presence felt in this election.

"Wouldn't we like to run against her?" Trump asked at his rally in Des Moines on Thursday. "Who's tougher? Her, crazy Bernie, Biden, Buttigieg, who would be the closest?"

"I don't know, maybe we take another crack at crazy Hillary would that be OK?" he said to roars of approval.

Clinton seems up for a rematch, too — and not just with Trump.

Clinton has kept an iron in the Democratic primary fire, from last year allowing rumors to spread that she might make a late-entry into race, to sharply criticizing Sanders and Rep. Tulsi Gabbard, D-Hawaii, to a media tour to promote a new documentary that happened to premiere at the Sundance Film Festival last weekend, days before the caucuses, which are set for Monday.

"I certainly feel the urge (to take on Trump again) because I feel the 2016 election was a really odd time and an odd outcome," she told Variety at Sundance, before adding she would work to support whoever wins the Democratic Party nomination.

The documentary, a four-part series based on 35 hours worth of interviews with Clinton, won't go public until March 6 when it appears on Hulu, but it's already caused controversy because of her remarks about Sanders: "Nobody likes him. Nobody wants to work with him. He got nothing done. He was a career politician," Clinton said. "It was all just baloney, and I feel so bad that people got sucked into it."

Her remarks, in addition to inciting a small firestorm, created an odd role-reversal, with left-wing activists playing the scolding grownups urging party unity and cooler rhetoric.

"In our collective fight against Donald Trump, we all have to be ready to support whoever the eventual Democratic nominee for president is," said Alexandra Rojas, the executive director of Justice Democrats. "Defeating Trump is far more important than settling old scores."

Meanwhile, other 2020 Democrats candidates wanted nothing to do with the controversy, declining to defend Clinton nor Sanders.

"I didn't love going through the experience of our party divisions in the past, Buttigieg, the told reporters in Mt. Pleasant, Iowa, last week. "I'm focused now on making sure that the future is better."

"I'm not going there," Massachusetts Sen. Elizabeth Warren said when asked about it by CBS News.

Obama is a frequent touchstone among the other candidates, whose legacy and whether it's being sufficiently respected has been much debated.

Buttigieg has been not-so-subtly reminding Iowans that they gave a chance to "a young man with a funny name" 12 years ago when they picked Obama over Clinton in the 2008 caucuses, and he's asking them to "make history" again by selecting him.

Biden, of course, mentions his former boss all the time — in ads, on the stump, in interviews, and everywhere in between.

He doesn't talk about Clinton, though he has brought up a study conducted by Harvard researchers which found that policy issues made up just 4 percent of media coverage of campaign the 2016 campaign between Trump and Clinton. "Debating me, running with me, it's going to be 94 percent," he said of the race he hoped to run against Trump.

And when a voter in Iowa earlier this month asked Biden if he was running a better campaign than Clinton, he gave a long answer before saying sexisim hurt Clinton in 2016. "That's not going to happen with me," he said.

Rep. Conor Lamb, who won a high-profile special election in a part of Western Pennsylvania that voted for Trump and is now supporting Biden, wouldn't criticize Clinton by name, but suggested Biden would play in the Rust Belt than her.

"There's a trust deficit. Folks used to vote for Democrats before. They still do at the local level," Lamb told NBC News. "But there's something about national Democratic leaders that they haven't liked in recent elections. And I think vice President Biden reminds them of the Democratic Party of old."

The women candidates, meanwhile, have begunleaning into their gender and the chance for voters to finally elect the first woman president in the final days of the race. But they don't bring up Clinton or riff on the 66 million cracks she put in the proverbial glass ceiling — the number of votes she won against Trump, which was enough to win the popular vote but lose the electoral college.

Democratic voters here, express a mix of admiration, disappointment and even some hostility to Clinton

But Karl Stoppel, who has caucused for pretty much everyone except Clinton — In 2008, he was for Biden, then Obama when he was forced to make a second choice and in 2016 he went for Sanders — but doesn't blame Clinton for losing to Trump.

"I think any Democrat would have gotten steamrolled by Donald Trump," he said.