No decision is too small for Bernie Sanders’ involvement. He has written his own Facebook posts; he weighs in on restaurant choices for the office holiday party; and he has been known to art-direct his photo ops.

But now, as he runs a sprawling operation that spans across multiple states and includes more employees than he could possibly manage himself, he’s had to learn to let go of the little things – or at least try to. The presidential candidate has had a hard time repressing his inner micromanager, according to more than a half dozen current and former aides, who both admire and sometimes feel frustrated by his hands-on style.

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Sanders has so far succeeded at wearing multiple hats, but even some close to him worry something will get dropped as he puts increasing demands on himself and his time, which could lead to burnout. But his management style is a product of his outsider upbringing in politics and as gotten him this far, so will he change it now when things matter most?

“He has always been a hands-on campaigner. He has had the people who have had the title of campaign manager, but he is always his own campaign manager.” Terry Bouricius, a longtime Sanders ally

Almost everybody who runs for president struggles to strike a balance between delegation and personally managing the large operations that get built around them, but some have more difficulty than others. “I think I could probably do every job on the campaign better than the people I’ll hire to do it,” Barack Obama once told David Plouffe, the man he would later hire to run his presidential campaign. “It’s hard to give up control when that’s all I’ve known.”

Plouffe eventually convinced Obama to “let go and trust” his staff, as the operative wrote in his book, “The Audacity to Win.”

“The most precious resource in any campaign is time. The candidate’s time,” Plouffe told Obama.

It wasn’t easy for Obama, and it might be even harder for Sanders. “He has always been a hands-on campaigner. He has had the people who have had the title of campaign manager, but he is always his own campaign manager,” said Terry Bouricius, a longtime Sanders ally and former aide who served in the Vermont House of Representatives. Sanders wants to approve “every single everything,” Bouricius added, “so it’s a bigger change of gears for him than it is for most people.”

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Not long ago, Sanders knew everyone in his Senate office, including what they did. Now, his New Hampshire team alone is about the size of that office, and he’s had to learn to delegate many managerial duties, like hiring for more junior positions, that he would otherwise like to be involved in.

With two full-time jobs – being a senator and running for president – the demands on his time are greater than ever. “What he’s going to have to do is a juggling act every single day to fulfill all of those roles,” acknowledged Tad Devine, Sanders’ top strategist, who has worked with the senator for years.

The piece that will be last to slip from Sanders’ grip, if it ever does, is his message. He still writes his own speeches, often longhand on a yellow legal pad. He regularly returns drafts of press releases to his staff with major edits he makes personally. And he dictates many of his campaign’s Tweets.

Sanders lets few people speak on his behalf, and thus keeps a grueling schedule packed with media appearances and lengthy stump speeches. (Advisers have worked with him on modulating the volume of his voice, both for rhetorical effect, but also to preserve his vocal chords.)

When MSNBC called a staffer who handles Sanders’ social media accounts to ask for an example of his boss’ hands-on approach, the aide was interrupted by a call on the other line. It was Sanders. He wanted to make sure the campaign’s new TV ad would be posted to Facebook.

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“I field a call like that four or fives times a day,” the aide chuckled, speaking on the condition anonymity. “Old habits die hard, and he’s still a very involved boss. Even running a national campaign, he’s still very involved in the daily grunt work.”

“What he’s going to have to do is a juggling act every single day to fulfill all of those roles.” Tad Devine, Sanders’ top strategist

As a content writer, the septuagenarian fittingly broke all the best practices rules, but still managed to flummox the millennial-aged social media professionals on his staff when his posts performed better than theirs.

Sanders keeps close tabs on his Twitters followers and Facebook “likes,” and carefully studies which messages generate the largest responses. Aides say its important feedback data for Sanders, the same way ropeline conversations are for other politicians.

The attention to detail grew out of his early years in politics, when it was both a necessity and a preference that set him apart from candidates who hired professional political consultants.

He’s a political autodidact. He had no money and no political party, so Sanders did “everything ‘in-house,’ usually my house,” as he wrote in his 1997 autobiography. He wrote radio ads around his kitchen table with his wife and friends, and turned to two local filmmakers to make his first TV ad. Two of his closest advisers were a religion professor and a poetry professor, so Sanders learned the mechanics of politics himself.

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And it worked; he won four mayoral races, eight House elections, and two in the Senate. “If you’ve taken a hands-on approach to all of your campaigns, and you keep winning, the feedback you get from the world is, keep doing that,” said Bouricius.

Supporters say the attention to detail makes Sanders a better and more committed advocate for his constituents and his ideas. And that he makes up for any inefficiency by just working himself harder. Still, it raises questions about whether he can be an effective CEO of a full-fledged presidential campaign, let alone the U.S. government, which requires a tremendous amount of delegation.

And could all the travel and speeches and attention to micromanagement push Sanders to a breaking point? “Your question is ‘Is he pushing himself too hard?’ Yeah, he always pushes himself too hard,” said Huck Gutman, one of Sanders’ oldest friends and his former chief of staff.