For more than two years, Hillary Clinton has been Democrats’ sure-thing next presidential nominee, while Republicans sorted through a messy and expansive field of wannabes.

Yet now, she’s dealing with an interminable primary, as the GOP’s new presumptive nominee Donald Trump trains his sights on her.

The sudden departures of Sen. Ted Cruz and Gov. John Kasich from the Republican race – which came sooner than Clinton aides expected – coupled with Sen. Bernie Sanders’ decision to stay in the race, creates a new challenge for Clinton, who now has to defend herself on two flanks.

“I’m still trying to come to terms with the fact that any Republican, let alone Donald Trump, was able to solidify the nomination before she was,” said Patrick Murray, the polling director at Monmouth University. “This makes it really tough for her. There’s no feasible way for Bernie Sanders to win the nomination, yet his decision to fight on in anything more than just a token way means she’s got to continue to expend resources in places that she wouldn’t bother.”

Clinton and her campaign have adopted a posture of benign indifference to Sanders, largely ignoring him and declining to engage his attacks. Meanwhile, they’ve pulled resources away from the primary to devote to the general election, and have already been engaging consistently with Trump.

That strategy won’t change now, campaign officials say, even as the primary technically continues for another five weeks. Despite Sanders’ upset victory in Indiana Tuesday, he remains a non-threat. Trump is now public enemy number one inside Clinton’s Brooklyn headquarters.

“Yes, it’s a two-front fight, but not evenly so,” said Tracy Sefl, a former aide to Clinton’s 2008 presidential campaign. “With Hillary poised to secure the nomination, her approach to Sanders is justifiably laissez-faire. With Trump, everyone is readying for DEFCON 1.”

Clinton is going to need Sanders’ supporters in the general election and will do nothing to push them away, even while she looks over Sanders’ head to Trump.

“I’m not calling myself [the presumptive nominee],” Clinton said in her first comments after the Indiana primary Wednesday, in an interview with CNN. “I know there are still some contests ahead and I respect Senator Sanders and whatever choices he make.”

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At a time when many Democrats are champing at the bit for Sanders to step aside, Clinton is sanguine. “I have a lot of empathy about this. You know, I ran till the very end in 2008,” she said.

The nightmare scenario for Democrats is the 1980 election, when then-Sen. Ted Kennedy fought incumbent President Jimmy Carter through to a brutal battle on the floor of the Democratic National Convention in New York City. That fight was thought to have weakened Carter and contribute to his eventual loss to Ronald Reagan in the fall. But few think 2016 will go down like 1980.

Veteran Democratic strategist Bob Shrum wrote Kennedy’s famous concession speech at the convention. He said Clinton can now begin assuming the mantle of the party’s spokesperson and standard bearer, even while allowing Sanders continue unmolested.

“She can’t deal with him in any way other than with kid gloves,” said Shrum. “That means room and respect for him to run all the way to the convention if she wants.”

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Democratic voters seem to be enjoying this primary and want it to continue.

Still, Sanders could distract, delay and potentially damage Clinton while Trump gets a head start on the general election.

Trump has already said he’ll use Sanders’ attacks on Clinton against her, especially his comment that the former secretary of state is unqualified to be president. (Clinton is doing the same with Trump’s opponents).

The likely Democratic nominee’s schedule over the next month will be dictated by the primary calendar, and it takes her through just a single battleground state, and a minor one at that: New Mexico. The rest of the trail passes through either safe Democratic states – like California, New Jersey and Oregon – or bright red Republican ones, like West Virginia and the Dakotas.

Clinton won’t be likely to campaign in these states in a general election, so any time and money spent in them now could be seen as a waste.

California’s size makes it a notoriously expensive place to run campaigns, but it would look terrible for Clinton to lose there, even if she still won the nomination. “You don’t want to end this by losing in the biggest and most reliably democratic state in the union,” said Shrum.

Clinton has, for the moment at least, stopped spending any money on television advertising in any of the remaining primary states to preserve that money for the general. That could change, especially after some question her campaign’s decision to cede the airwaves to Sanders in Indiana. Her campaign has already been rolling out officials to run her general election campaign in key battleground states like Ohio and Florida.

But as long as Clinton has to stay in the primary, she might as well make it count, said Mo Elleithee, a former Democratic National Committee official who now runs Georgetown University’s Institute of Politics.

Clinton can use the remaining primaries and caucuses as tools to develop her messaging and organizational prowess for the general. “In 2008, John McCain was the nominee in March, and we kept going all the way to June. And at the end of the day it was the best thing for the Democratic Party,” Elleithee said.

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Indeed, Sanders allies say he’s actually doing her a favor by staying in the race.

Rep. Raul Grijalva, Sanders’ first congressional endorser, said if Sanders were to drop out now, he would leave a large chunk of the Democratic base feeling like they don’t have a home in the Democratic Party.

“It’s not like the Bernie people are going to run to Trump. What they’d do is not vote,” he said. “Instead of getting the support that you need going into the general, you’d get disillusionment.”

It’s better for Clinton and all Democrats, he said, for Sanders to say in to make sure his supporters feel appreciated by securing some kind accommodation at the convention, like a chance to the platform or nominating process.

“Finishing it out, going to the convention strengthens the party because everyone stays in the tent,”Grijalva said.