When Bernie Sanders mounted his initial Senate run in 2006, then-Senator Barack Obama came to Vermont to campaign for him.Toby Talbot / AP

Updated at 4:11 p.m. ET on February 19, 2020.

Bernie Sanders got so close to running a primary challenge to President Barack Obama that Senator Harry Reid had to intervene to stop him.

It took Reid two conversations over the summer of 2011 to get Sanders to scrap the idea, according to multiple people who remember the incident, which has not been previously reported.

That summer, Sanders privately discussed a potential primary challenge to Obama with several people, including Patrick Leahy, his fellow Vermont senator. Leahy, alarmed, warned Jim Messina, Obama’s presidential reelection-campaign manager. Obama’s campaign team was “absolutely panicked” by Leahy’s report, Messina told me, since “every president who has gotten a real primary has lost a general [election].”

David Plouffe, another Obama strategist, confirmed Messina’s account, as did another person familiar with what happened. (A spokesman for Leahy did not comment when asked several times about his role in the incident.)

Messina called Reid, then the Senate majority leader, who had built a strong relationship with Sanders but was also fiercely defensive of Obama. What could you be thinking? Reid asked Sanders, according to multiple people who remember the conversations. You need to stop.

Sanders didn’t end up running against Obama. But their relationship didn’t improve in the years that followed. In another incident, in 2013, Sanders laid into Obama in a private meeting he held with Democratic senators, saying that the president was selling out to Republicans over Social Security benefits. (More on that incident, which has also not been previously reported, below.)

Now Obama, the beloved former leader of the Democratic Party, and Sanders, the front-runner for the Democratic presidential nomination, are facing a new and especially fraught period in their relationship. To Obama, Sanders is a lot of what’s wrong with Democrats: unrelenting, unrealistic, so deep in his own fight that he doesn’t see how many people disagree with him or that he’s turning off people who should be his allies. To Sanders, it’s Obama who represents a lot of what’s wrong with Democrats: overly compromising, and so obsessed with what isn’t possible that he’s lost all sense of what is.

Obama has made clear in private conversations that he doesn’t like the idea of Sanders as the nominee (and has been only slightly more subtle in public comments), but he’s pushed back on some who have urged him to get involved, anxious that any move he makes could destroy the hope of him using his unique position to unite the party and defeat Trump during the general election. In a party this divided, Obama- and Sanders-style Democrats finding a connection may be the only way to win in November.

Obama is determined to make it work—if he has to.

“Obama has several friends and former colleagues in the race but believes that in order for the Democratic Party to be successful, voters will have to pick their candidate,” a person close to Obama told me. “Obama will campaign his heart out for whoever the nominee is, and that includes Senator Sanders.”

Obama and Sanders’s political relationshIP dates back to 2006, when Sanders showed up in Obama’s Senate office asking for a favor: Would Obama come up to Vermont to campaign for him? Obama had barely been in Washington a year, hadn’t started running for president, and he was already being called a disappointment by some liberal Democrats. But he was a superstar, already the most in-demand Democrat in the country, and he was an important stamp of approval for a democratic socialist aiming to be the de facto Democratic nominee in his state’s Senate race.

Obama agreed, and arrived on an unseasonably warm day in March 2006 for a fundraiser and rally at the University of Vermont, before a crowd of cheering students. Sanders called Obama a great leader of the Senate. Obama called Sanders a force against cynicism and said the state should send him and soon-to-be-elected Representative Peter Welch to Washington to “keep on stirring up some trouble.”

Sanders didn’t endorse or campaign for Obama in the 2008 Democratic presidential primary, though Obama went on to beat Hillary Clinton in Vermont with 59 percent of the vote.

Sanders aides have long dismissed the idea that the senator was serious about a primary challenge to Obama in his re-election—“he was asked a question on a progressive radio show” is how Jeff Weaver, his closest aide, argued to me last week. Weaver was referring to an interview Sanders gave on Thom Hartman’s radio show in July 2011, when the senator said, “There are millions of Americans who are deeply disappointed in the president—who believe that, with regard to Social Security and a number of other issues, he said one thing as a candidate and is doing something very much else as a president; who cannot believe how weak he has been, for whatever reason, in negotiating with Republicans; and there’s deep disappointment.” He continued: “It would be a good idea if President Obama faced some primary opposition.”

That was not the only time Sanders raised the idea publicly. Appearing on C-SPAN a few weeks later, he expanded on the point: “They want the president to stand up for the middle class, for the working class of this country, and they want him to take on big-money interests in a way that he has not done up to this point.” He’d been talking up a primary challenge since at least that spring, when he said in a radio interview with WNYC that he was already being asked whether he’d run against Obama, and although he insisted that he wasn’t going to, “in a democracy, it’s not a bad idea to have different voices out there.”

Criticism of Obama from the left, while not representative of the opinions of most Democrats, was not unusual at the time. Left-leaning activists pushed the president on issues such as foreclosure relief, judicial nominations, and drone strikes. In August 2011, just as Reid was being called in to to help stop Sanders’s primary plans, David Sirota—a former Sanders press secretary who remained plugged in to the senator’s thinking during the Obama years and would join Sanders’s 2020 campaign as a senior adviser and speechwriter—wrote that Obama was “eloquent, dissembling, conniving, intelligent and, above all, calm,” and was using those traits in service of being “a Bizarro FDR” with a “hideous and destructive” record.

Weaver did not respond to multiple requests to comment on Reid’s 2011 conversations with Sanders. After this story was published, Ari Rabin-Havt, Sanders’s deputy campaign manager, emailed with an additional statement: "It never crossed his mind to challenge Obama,” Rabin-Havt said. “Bernie was running for re-election in 2012 and that’s what he was focused on.”

Reid declined to speak about the episode on the record. Asked specifically about the Sanders campaign's insistence that the 2011 conversations never happened, a Reid spokesperson did not deny that the former majority leader talked Sanders down. Reid “won’t get into private conversations,” the spokesperson said. “Bottom line: there was never a serious or established primary challenge to Obama from anyone.” (Afterward, the spokesperson sent along an additional comment from Reid himself: “Bernie was running for reelection in 2012. He would’ve been a fool to run against Obama and Bernie’s no fool," he said.)

On the rare occasions Obama White House staff thought about Sanders, it was because he was needling or annoying them, several former Obama aides recalled. Before Sanders started running for president, he had never been to see Obama in the Oval Office. And even though most of them didn’t know how far Sanders’s primary plans had gone, Obama aides took notice of his public comments. Today, the bitterness lingers.

“It’s not to say they had a bad relationship when Obama got to the White House,” one person who worked for Obama in the West Wing told me. “It’s just that they didn’t have a relationship.”

Obama and his circle tend to see Sanders’s You’re with us or you’re wrong approach as unworkable and the criticism of his own record as president overrepresented on Twitter (Obama’s approval rating among Democrats is consistently in the 90s).

The low point between the two men was a 2013 meeting with other Democratic senators. Obama had just put a chained Consumer Price Index in his budget, a proposal that would cut Social Security benefits by tying them to the rate of inflation. Many Senate Democrats were angry about it. But when they arrived for the meeting, it was Sanders who bubbled up, ripping into Obama for giving in to Republicans and not understanding the impact of the cuts.

“I don’t need a lecture,” Obama told him, according to several senators who attended the meeting.

Sanders proceeded to give him one anyway. A number of the senators there were struck by what they told me seemed like a lack of respect.

“Obama fairly forcefully pushed back and said, ‘That’s just not right—that’s not a vision that’s enactable or possible,’” one senator in the room recalled, asking for anonymity to discuss the private meeting. “‘You’re acting like I’m the enemy.’ Obama was trying to say, ‘I hear you that you want this revolution, but explain to me, how’s this going to happen? Look at the current makeup of the Senate and the House. How am I supposed to lead?’” Obama said, in this senator’s memory. The conversation quickly got testy. “It seemed the match of someone who prided himself on his cool intellect and removed analysis versus someone who was convinced with absolute ferocity with the rightness of his worldview and is not given to accepting anything from those who don’t agree with it.”

“I just remember thinking, Whoa, Bernie’s got game,” a second senator who was in the room told me. “I also remember thinking, There’s no love lost between them.”

In the end, most of the caucus took the position that Sanders voiced, opposing the chained Consumer Price Index, and Obama relented and dropped the idea. That was Sanders and Obama’s last substantive discussion before Sanders started winning support in his 2016 presidential run. Alumni of the Obama West Wing whom I spoke with had trouble remembering any time when they were in touch with Sanders or his staff for anything significant, even around the 2014 passage of a bipartisan veterans’-health bill, which is generally regarded as the most significant legislation Sanders got through Congress.

Obama and Sanders have worked to improve their relationship since Obama left office, starting with a one-on-one meeting in 2018, when they discussed their ideas about what Democrats should be working on, what counted as practical, and what counted as idealistic.

Their views did not line up, people familiar with the conversation told me afterward. But the men share a respect for the political movement the other has built.

“Bernie has an admiration for how Obama ran his 2008 campaign and the way he built a strong grassroots movement behind him. He has an admiration and true and deep respect for the president,” Rabin-Havt told me.

In public, Obama has distanced himself from Sanders, warning in November that there’s a difference between “left-leaning Twitter feeds” and persuadable voters, and that “this is still a country that is less revolutionary than it is interested in improvement.” But in private, he’s expressed similar admiration for Sanders’s movement, in 2016 and now.

“They may have their differences, but one thing Obama admires about Sanders is his ability to galvanize his supporters, both online and offline. President Obama has been impressed by that,” the person close to Obama told me.

Sanders’s team is also trying to downplay past disagreements. “Barack Obama gets hit a little too hard,” Jeff Weaver told me. “Anybody who came into office facing the potential of a worldwide economic meltdown—it’s a very, very difficult situation to be in. And, you know, he helped avoid that. Bernie Sanders was not overly critical. They would have approached things a little bit differently, that’s all.”

I pressed Weaver, pointing out that some people who support Sanders and have worked on his campaign have a negative view of Obama, and feel that Obama gave in to Republicans and moderates too much. “That’s certainly not my view, and I don’t believe it’s Bernie Sanders’s view,” he said.

A few days later, I reached out again, first by phone and then by text. Initially, Weaver responded. But when I told him I’d found out about Reid’s intervention to stop Sanders from mounting a primary challenge in 2011, he stopped responding.

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