BURLINGTON, VERMONT (CNN) Bernie Sanders, the man who is leading in New Hampshire and giving Hillary Clinton a run for her money in Iowa, is coming to terms with a new reality: The media is taking him seriously.

Since launching his campaign last May, Sanders has received vastly less media attention than his chief Democratic opponent, while his chances of becoming the party's nominee were largely dismissedby pundits and commentators — despite the fact that, like a certain senator before him, he draws far larger crowds, boasts a remarkably enthusiastic volunteer base,and, though he doesn't have as much money as Clinton, set an all-time record with more than 2.3 million campaign contributions last year.

Now, with Sanders climbing in the polls two weeks before the Iowa caucuses — and likely to maintain momentum after a strong debate performance on Sunday — the mainstream media is racing to catch up to a phenomenon that has been abundantly clear to backers, donors and the progressive media for nine months.

Biden greets Sanders with an elbow bump before the start of a debate in Washington in March 2020. They went with an elbow bump instead of a handshake because of the coronavirus pandemic.

Biden greets Sanders with an elbow bump before the start of a debate in Washington in March 2020. They went with an elbow bump instead of a handshake because of the coronavirus pandemic.

Sanders speaks to reporters in Burlington, Vermont, a day after Super Tuesday II. Sanders said it "was not a good night for our campaign from a delegate point of view" but that he looked forward to staying in the race and taking on Joe Biden in an upcoming debate.

A triumphant Sanders raises his fist in San Antonio after he was projected to win the Nevada caucuses.

Sanders laughs during a primary-night rally in Manchester, New Hampshire, in February 2020. Sanders won the primary, just as he did in 2016.

In a tense and dramatic exchange moments after a Democratic debate, Warren accused Sanders of calling her a liar on national television. Sanders responded that it was Warren who called him a liar. Earlier in the debate, the two disagreed on whether Sanders told Warren, during a private dinner in 2018, that he didn't believe a woman could win the presidency.

US Rep. Alexandria Ocasio-Cortez introduces Sanders at a New York rally after endorsing him for president in October 2019.

US Rep. Alexandria Ocasio-Cortez introduces Sanders at a New York rally after endorsing him for president in October 2019.

Sanders campaigns at the University of New Hampshire in September 2019. A few days later, he took himself off the campaign trail after doctors treated a blockage in one of his arteries. Sanders suffered a heart attack, his campaign confirmed.

Sanders grabs the hand of US Sen. Elizabeth Warren during the Democratic debates in Detroit in July 2019.

Sanders grabs the hand of US Sen. Elizabeth Warren during the Democratic debates in Detroit in July 2019.

Sanders speaks next to former Vice President Joe Biden at the first Democratic debates in June 2019.

Sanders speaks next to former Vice President Joe Biden at the first Democratic debates in June 2019.

Sanders looks at his notes as he watches President Trump deliver the State of the Union address in February 2019. That month, Sanders announced that he would be running for president again.

Sanders looks at his notes as he watches President Trump deliver the State of the Union address in February 2019. That month, Sanders announced that he would be running for president again.

Sanders brings a giant printout of one of Donald Trump's tweets to a Senate debate in January 2017. In the tweet, Trump had promised not to cut Social Security, Medicare and Medicaid.

Sanders speaks at a rally in Santa Monica, California, in June 2016. He pledged to stay in the Democratic race even though Clinton secured the delegates she needed to become the presumptive nominee.

Sanders speaks at a rally in Santa Monica, California, in June 2016. He pledged to stay in the Democratic race even though Clinton secured the delegates she needed to become the presumptive nominee.

Sanders speaks at a campaign rally in Ann Arbor, Michigan, in March 2016. He won the state's primary the next day, an upset that delivered a sharp blow to Clinton's hopes of quickly securing the nomination.

Sanders and his wife, Jane, wave to the crowd during a primary night rally in Concord, New Hampshire, in February 2016. Sanders defeated Clinton in the New Hampshire primary with 60% of the vote, becoming the first Jewish candidate to win a presidential primary.

Comedian Larry David and Sanders appear together on "Saturday Night Live" in February 2016. David had played Sanders in a series of sketches throughout the campaign season.

Sanders sits with rapper and activist Killer Mike at the Busy Bee Cafe in Atlanta in November 2015. That evening, Killer Mike introduced Sanders at a campaign event in the city. "I'm talking about a revolutionary," the rapper told supporters. "In my heart of hearts, I truly believe that Sen. Bernie Sanders is the right man to lead this country."

Sanders embraces Remaz Abdelgader, a Muslim student, during an October 2015 event at George Mason University in Fairfax, Virginia. Asked what he would do about Islamophobia in the United States, Sanders said he was determined to fight racism and "build a nation in which we all stand together as one people."

Sanders embraces Remaz Abdelgader, a Muslim student, during an October 2015 event at George Mason University in Fairfax, Virginia. Asked what he would do about Islamophobia in the United States, Sanders said he was determined to fight racism and "build a nation in which we all stand together as one people."

Seconds after Sanders took the stage for a campaign rally in August 2015, a dozen protesters from Seattle's Black Lives Matter chapter jumped barricades and grabbed the microphone from the senator. Holding a banner that said "Smash Racism," two of the protesters -- Marissa Johnson, left, and Mara Jacqueline Willaford -- began to address the crowd.

In July 2015, two months after announcing he would be seeking the Democratic Party's nomination for President, Sanders spoke to nearly 10,000 supporters in Madison, Wisconsin. "Tonight we have made a little bit of history," he said. "You may know that some 25 candidates are running for President of the United States, but tonight we have more people at a meeting for a candidate for President of the United States than any other candidate has."

In March 2015, Sanders speaks in front of letters and petitions asking Congress to reject proposed cuts to Social Security and Medicare.

In March 2015, Sanders speaks in front of letters and petitions asking Congress to reject proposed cuts to Social Security and Medicare.

Sanders and US Rep. Jeff Miller, chairman of the House Committee on Veterans' Affairs, walk to a news conference on Capitol Hill in 2014. Sanders was chairman of the Senate Committee on Veterans' Affairs.

Sanders and US Rep. Jeff Miller, chairman of the House Committee on Veterans' Affairs, walk to a news conference on Capitol Hill in 2014. Sanders was chairman of the Senate Committee on Veterans' Affairs.

Sanders speaks to reporters in 2010 about the Obama administration's push to extend Bush-era tax cuts. Three days later, Sanders held a filibuster against the reinstatement of the tax cuts. His speech, which lasted more than eight hours, was published in book form in 2011. It is called "The Speech: A Historic Filibuster on Corporate Greed and the Decline of Our Middle Class."

Sanders speaks to reporters in 2010 about the Obama administration's push to extend Bush-era tax cuts. Three days later, Sanders held a filibuster against the reinstatement of the tax cuts. His speech, which lasted more than eight hours, was published in book form in 2011. It is called "The Speech: A Historic Filibuster on Corporate Greed and the Decline of Our Middle Class."

Sanders chats with Dr. John Matthew, director of The Health Center in Plainfield, Vermont, in May 2007. Sanders was in Plainfield to celebrate a new source of federal funding for The Health Center.

Sanders chats with Dr. John Matthew, director of The Health Center in Plainfield, Vermont, in May 2007. Sanders was in Plainfield to celebrate a new source of federal funding for The Health Center.

Sanders takes part in a swearing-in ceremony at the US Capitol in January 2007. He won his Senate seat with 65% of the vote.

Sanders takes part in a swearing-in ceremony at the US Capitol in January 2007. He won his Senate seat with 65% of the vote.

Sanders sits next to President Bill Clinton in 1993 before the Congressional Progressive Caucus held a meeting at the White House. Sanders co-founded the caucus in 1991 and served as its first chairman.

Sanders sits next to President Bill Clinton in 1993 before the Congressional Progressive Caucus held a meeting at the White House. Sanders co-founded the caucus in 1991 and served as its first chairman.

In 1990, Sanders defeated US Rep. Peter Smith in the race for Vermont's lone House seat. He won by 16 percentage points.

In 1990, Sanders defeated US Rep. Peter Smith in the race for Vermont's lone House seat. He won by 16 percentage points.

Sanders reads mail at his campaign office in Burlington in 1990. He was running for the US House of Representatives after an unsuccessful bid in 1988.

Sanders reads mail at his campaign office in Burlington in 1990. He was running for the US House of Representatives after an unsuccessful bid in 1988.

In 1987, Sanders and a group of Vermont musicians recorded a spoken-word folk album. "We Shall Overcome" was first released as a cassette that sold about 600 copies. When Sanders entered the US presidential race in 2015, the album surged in online sales. But at a CNN town hall, Sanders said, "It's the worst album ever recorded."

Sanders, right, tosses a baseball before a minor-league game in Vermont in 1984. US Sen. Patrick Leahy, center, was also on hand.

Sanders, right, tosses a baseball before a minor-league game in Vermont in 1984. US Sen. Patrick Leahy, center, was also on hand.

Sanders takes the oath of office to become the mayor of Burlington, Vermont, in 1981. He ran as an independent and won the race by 10 votes.

Sanders takes the oath of office to become the mayor of Burlington, Vermont, in 1981. He ran as an independent and won the race by 10 votes.

Sanders, right, leads a sit-in organized by the Congress of Racial Equality in 1962. The demonstration was staged to oppose housing segregation at the University of Chicago. It was Chicago's first civil rights sit-in.

Sanders, right, leads a sit-in organized by the Congress of Racial Equality in 1962. The demonstration was staged to oppose housing segregation at the University of Chicago. It was Chicago's first civil rights sit-in.

US Sen. Bernie Sanders speaks at a campaign rally in Chicago in March 2019. Sanders, an independent from Vermont, is the longest-serving independent in the history of Congress.

US Sen. Bernie Sanders speaks at a campaign rally in Chicago in March 2019. Sanders, an independent from Vermont, is the longest-serving independent in the history of Congress.

"Clearly, we were not getting coverage that was commensurate with our support among the electorate," Jeff Weaver, Sanders' campaign manager, said during an interview here at Hotel Vermont, where Sanders was preparing for Sunday's debate, the last before the Iowa caucuses on February 1. "Is it a frustration? Of course it's a frustration."

The failure to anticipate Sanders' rise points to a deep flaw with American political media, journalists and campaign strategists told CNN: Despite being proven wrong time and time again, many commentators and reporters continue to cling to an unshakeable faith in the conventional wisdom about the campaign while often ignoring realities on the ground.

In this case, conventional wisdom held that Clinton would waltz to the Democratic nomination without being seriously contested. The only thing that could possibly get in her way was Vice President Joe Biden (who ultimately decided not to run) or her own controversies. But a grumpy 74-year-old Democratic socialist from Vermont with a bag full of expensive left-wing policy nostrums? Not a chance.

Where the press went wrong

The presidential campaign has been rife with such examples of faulty establishment media-think, from the early insistence that Jeb Bush would be the Republican candidate to beat to the oft-repeated claim that Donald Trump's latest incendiary claim was political suicide.

"Pundits and the press have been wrong about just about everything this cycle, and this falls into that category," Dan Pfeiffer, a former senior adviser to President Barack Obama who now serves as a CNN contributor, said of Sanders' rise.

Photos: Democratic debate in Charleston Photos: Democratic debate in Charleston Candidates Martin O'Malley, Hillary Clinton and Bernie Sanders take part in the final Democratic presidential debate before the caucuses. Hide Caption 1 of 6 Photos: Democratic debate in Charleston Clinton and Sanders began the evening trading barbs on gun control. Clinton slammed Sanders for voting "with the NRA, with the gun lobby numerous times." Sanders hit back, arguing that he had a D-minus voting rating from the National Rifle Association and rejected her list of charges. Hide Caption 2 of 6 Photos: Democratic debate in Charleston Clinton and Sanders also argued over health care. "We finally have a path to universal health care, we have accomplished so much already. I do not want to see the Republicans repeal it and I don't want us to start all over again with a contentious debate," said Clinton. Hide Caption 3 of 6 Photos: Democratic debate in Charleston Sanders angrily rejected Clinton's claims that his plans would result in the gutting of Obamacare, saying that he wanted to build on the achievements of the current president, not overturn them. "No one is tearing this up, we are going to go forward," Sanders said, his voice rising in anger. "That is nonsense." Hide Caption 4 of 6 Photos: Democratic debate in Charleston A new NBC/Wall Street Journal national poll on Sunday showed Clinton leading Sanders 59% to 34%, with the third candidate in the race, former Maryland Gov. Martin O'Malley, at 2%.

Hide Caption 5 of 6 Photos: Democratic debate in Charleston Martin O'Malley delivered a dig at the GOP candidates, recounting a voter asking him to not refer to her son, who serves in the military, as a pair of boots on the ground. O'Malley said Republicans use, "boots on the ground," when they're "trying to look all bravado and macho sending other peoples' kids into combat." Hide Caption 6 of 6

"People did not pay as much attention to him or take him seriously in the beginning because he is an older politician from a small state who they did not know much about," said April Ryan, the Washington bureau chief for American Urban Radio Networks.

The dismissal of Sanders, including on occasion by CNN as well as other outlets, is especially palpable for his supporters, who feel like the candidate was written off because of both his temperament and his political beliefs.

When Sanders announced his bid, a Washington Post profile described the "unlikely presidential candidate" as "an ex-hippie, septuagenarian socialist from the liberal reaches of Vermont who rails, in his thick Brooklyn accent, rumpled suit and frizzy pile of white hair, against the 'billionaire class' taking over the country." The New York Times — which had afforded its front page to similar candidacy announcements from Clinton, Donald Trump, Ted Cruz and others — buried the Sanders story on page 21.

Sanders, however, immediately began drawing thousands of supporters, and then tens of thousands, to his rallies. The media acknowledged the large crowds, but the Sanders campaign felt that pundits came up with endless ways to dismiss their importance.

"At every stop, the media had an explanation for why the crowds weren't significant," Weaver said. "5,000 people here? 'Oh, that's Bernie's home city.' New Hampshire, 'Oh, that's next door.' We went to Minneapolis and had 4,000 people -- 'Oh, well, that's the Frost Belt. Frost Belt people like him.' Then we went to Denver, and it was 'college liberals.'"

"Wherever we went, there was always an explanation about why what we were doing seemed to be significant, but really wasn't," Weaver said.

It wasn't that there weren't reporters or cameras at these events, Weaver explained. It was that, very often, none of the coverage showed up on the front page or on television. If you looked to the mainstream media, he said, you would have no idea that Sanders would one day be running even in Iowa or leading New Hampshire.

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Weaver noted two exceptions: Local media, which he said did a much better job of focusing on policy over process; and the progressive media — but neither of those could rival the overwhelming national narrative that Sanders was merely an also-ran.

Jonathan Tasini, a Sanders surrogate, called the coverage "a professional failure."

"It's both astonishing and understandable," Tasini said. "The understandable part is, too many journalists are too enthralled with conventional wisdom and establishment thinking. They just repeat things without any notion of what's happening on the ground."

Many reporters, who asked to speak on background so as not to offend their news organizations or their colleagues, agreed.

"Among 'big-time' reporters, there's an almost pathological fear of looking unsophisticated," one veteran political reporter explained. "Journalists are supposed to look 'wised-up' and with it. I think this ingrained tendency often causes us to miss things that should be as plain as the noses on our faces — and that are apparent to 'civilians.'"

Now that Sanders is a real contender in some early states, he is forcing the media to recognize the vast liberal base that exists to the left of the Democratic establishment, much as the rise of the tea party forced the press to focus on the vast conservative base to the right of the Republican establishment.

The media has not always been receptive to this wing of the Democratic party, the veteran journalist explained. "The media has an instinctive bias against ultra-liberals. The real hard liberals are not taken seriously by our tribe," he said. "No socialist from Vermont is going to be president, in the same way Howard Dean was written off."

The Clinton factor

Weaver also believes the media has an inevitable pro-Clinton bias because so many of the "Democratic consultants" who serve as pundits have relationships with the Clintons.

"Look at the political consultants on the air and Democratic pundits across the media. They're often Hillary Clinton supporters, right? Or former employees," he said. "That's not an indictment of anybody, but that makes them more open to a message that says, 'She's going to be successful. Bernie is not going to be successful.'"

If there was a moment in 2015 when Sanders could have wrested control of the media's narrative, Weaver said, it was in mid-October, when the Democrats met for their first debate, Biden was eyeing getting into the race, and Clinton was called to testify on the 2012 Benghazi attacks. But Clinton acquitted herself well in the debate and during the day-long congressional testimony and Biden decided not to run. Sanders, again, appeared an unworthy challenger.

"The Secretary had a very good October," Weaver conceded. "The first debate she performed very well, she showed well at the Benghazi hearing, and the media viewed the Vice President's decision not to run as favorable to her. That again created a narrative about Hillary's inevitability, which all the pundits repeated."

Several journalists on the campaign trail also conceded that the media had been too consumed by Donald Trump and the seismic Republican primary race that is dividing the GOP. Trump's dominance, the establishment's fear and disbelief, and the emerging fight for an alternative — coupled with the belief in Clinton's inevitability as the Democratic nominee — drew much of the media's attention away from the Democrats.

"The incredible and uncontrollable obsession with all things Trump has moved almost all of the scrutiny and focus to the GOP side of the equation once Clinton survived the Benghazi hearing and Biden dropped out," Pfeiffer said.

When asked to explain why the media had failed to anticipate Sanders' rise, one political editor at a Washington news outlet replied: "We knew Hillary was going to win, and we went chasing after Donald Trump."

That disparity has not been lost on Sanders. "A recent study showed on ABC evening news, Trump over a period of time got 81 minutes of time. Bernie Sanders got 20 seconds," Sanders said in an interview with CNN's Chris Cuomo in December. "Now, you tell me why."

Now that Sanders is giving Clinton a run for her money in Iowa and New Hampshire -- although he still trails badly in national polls, including one by NBC released Sunday that found Clinton with a 25-point edge -- things are changing.

At the Hotel Vermont, CBS's John Dickerson was there to interview Sanders for "Face The Nation" -- while Bloomberg's John Heilemann was busy setting up cameras for his own interview.

"I've never been in an avalanche, but I'm beginning to think I know what it feels like," Michael Briggs, Sanders' spokesperson, said of the media requests he was receiving.

Still, many members of the media maintain that while Sanders may win Iowa and New Hampshire, he cannot amass enough support, particularly among minorities, in subsequent states to actually put up a real fight against Clinton. (Sanders is already trying to remedy that with a media blitz in South Carolina focused on African Americans.)

Pfeiffer argued that Sanders is still "a very long shot to win the nomination" and likened him not to Barack Obama but to Howard Dean or Bill Bradley: "Anti-establishment candidates with a strong base in the largely white, progressive community who can do very well in Iowa and New Hampshire with no clear path to expanding their base."

But whether Sanders can win the nomination may be beside the point. The fact may be that, after being written off by the media, the 74-year-old Democratic socialist from Vermont is threatening to take both Iowa and New Hampshire from Hillary Rodham Clinton, a towering political figure with unparalleled experience, vast financial resources, and the backing of the Democratic establishment.

In other words, Sanders has come a long way from Page 21 and "the liberal reaches of Vermont" — and the media is finally taking note.