Competing in the largest primary field in history, 2020 Democratic presidential contenders are affiliating with labor unions and offering lavish benefits to campaign staff to attract talent and bolster their liberal bona fides.

But those employment decisions could spell disaster, leading to profligate spending and inflexible work schedules, handing a major boost to President Trump in the 2020 general election.

Traditionally, presidential campaigns are staffed by young political junkies who operate on little sleep and almost no money, fueled by their idealistic fervor and sustained by the hope that their selfless service could eventually be rewarded with a job in the White House.

In 2020, that is changing as campaign staff demand the type of pay and benefits more associated with 9-to-5 office jobs and commutes to and from suburbia.

Bernie Sanders, Elizabeth Warren, Cory Booker, and Julián Castro have all opted to allow their campaign workers to unionize. A fifth candidate, Eric Swalwell, had unionized staff affiliated with Teamsters Local 238 but dropped out, citing financial woes as one of the reasons he ended his campaign.

Even those without unionized employees are spending lavishly. Beto O'Rourke is offering a minimum starting salary for staffers in Iowa of $50,400, with regional field directors banking a minimum of $62,400.

Those who work on the former Texas congressman's campaign are also entitled to 12 weeks paid parental leave and a 3% donation to their 401(k) accounts, even if they don't contribute anything themselves. His campaign also has one of the highest burn rates. In the April-June quarter, O'Rourke's campaign spent $5.3 million, despite only raising $3.6 million.

"Campaigns are about using your resources wisely, when you run it like a Fortune 500 company," Alice Stewart, a veteran Republican consultant who worked on five presidential campaigns from 2008 to 2016, told the Washington Examiner.

"These kind of benefits aren't sustainable for a campaign and give a huge advantage to President Donald Trump who has virtually unlimited resources. These kind of benefits will be a real test of whether the Democrats' progressive policies can actually work," she said.

Following closely behind in rapid burn rates is Sen. Booker of New Jersey, who spent more than half of his last-quarter earnings on staff costs. He announced this week that his campaign, whose staff have demanded higher pay and better benefits, was unionizing, affiliating itself with Teamsters Local 238. This will likely drive up costs.

Unionization by the staffs of Sens. Sanders of Vermont and Warren of Massachusetts are already testing whether they can run effective presidential races with workers subject to working hour restraints and other restrictions. The Sanders campaign is affiliated with United Food and Commercial Workers Local 400, Elizabeth Warren's with International Brotherhood of Electrical Workers Local 2320, and Julián Castro with the Campaign Workers Guild.

Negotiations between Sanders and his campaign's collective bargaining unit in July led to heated exchanges between the two sides, a potentially ominous sign for the future.

"It does bother me that people are going outside of the process and going to the media," Sanders grumbled after outlets reports detailing complaints from his staff. "That is really not acceptable. It is really not what labor negotiations are about, and it's improper."

Days later, his campaign was hit with a federal labor complaint by an employee who alleged that management had engaged in illegal interrogation, repudiation, and modification of contract.

"What we're seeing so far from the bargaining disputes is demonstrative of why unionization has never taken hold in the political sector. Unlike manufacturing, these campaign jobs aren't the kind you hold onto for a long time, campaigns need to be dynamic," Employment Policies Institute managing director Michael Saltsman told the Washington Examiner.

"A unionized workforce is the opposite of at-will employment. These staffs will have lots of leverage throughout the campaign."

By last month, Sanders had 282 staff, all of whom, in addition to salaries, will have all their healthcare costs covered by the campaign. They formed a labor union in May. The current bargaining unit currently includes about 100 employees, although the union anticipates it could grow up to 1,000.

In June, Warren's campaign staff also agreed to unionize, although no contract has yet been agreed upon with management.

Guarantees in the Sanders campaign contract, which will likely be a template for Warren's campaign, include health benefits as well as a $15 minimum wage. Field organizers must be guaranteed $46,800 annually and regional field directors $62,400 annually, according to selected details released to media outlets by the Sanders campaign.

Those guarantees, the entirety of which have remained secret, are already proving costly. According to last quarter's Federal Election Committee filings by Sanders' campaign, it's spending a third of all its revenue on staff. Those expenses will undoubtedly rise as the campaign's size increases and the provisions of the union contract are fully implemented.

There will also be other unionization costs that Sanders, Warren, and Booker will have to carry. Sanders campaign staff negotiated 20 days paid vacation for all those in the collective bargaining agreement. Those in the union will also be entitled to breaks throughout the day.

Saltman said that those hourly limits, currently set at 42 a week, and breaks are unprecedented on a presidential campaign, and will mean more staff will have to be hired to fill in the gaps. Staff who relocate are entitled to a moving stipend.

"These contracts are about setting up norms and expectations. There's always going to be tensions about hours and compensation, but that's true whether there's a union contract or not," Rutgers University labor expert and former Service Workers International Union organizer Will Brucher told the Washington Examiner.

"It's a rather new political phenomenon, but it's a natural development when you have campaign workers working for people who say they're in favor of the labor movement," he said.

UFCW Local 400 Communications Manager Jonathan Williams told the Washington Examiner that Sanders staffers will also likely be entitled to wage increases as well as a formal arbitration process. Williams outlined a three-step "expedited" process in the cases of employee grievances, which includes formal meetings between management, mandatory arbitration with a binding ruling, and lastly, presumably, a strike.

Currently, Sanders has a staff of 48 in Iowa. That number will grow, with his 2016 campaign already operating 23 different offices throughout the state, when he lost narrowly to Democratic primary rival Hillary Clinton in 2016. At the height of his 2016 candidacy, he employed more than 900.

That 2016 number was eventually cut back to around 300. This time around Sanders may well have to deal with big expenditures when he sheds staff — employees will be entitled to at least 30 days severance, according to Williams. It remains unclear how this provision would work when he ends his campaign.

If even half of those staff end up in the union collective bargaining unit, scaling back employees could cost millions in severance pay, leaving Sanders with a major financial headache at a time when, if he is the Democratic nominee, he is preparing to face Trump in November 2020.

A spokesman for Joe Biden said in May that “if staff decided they wanted to unionize, the vice president would welcome it.”