Cody Eliff says he waited in the selfie line for over an hour after a recent rally in Iowa City just to spend a few moments with Elizabeth Warren.

When the time came, he got more than just a trademark selfie with the surging Democratic candidate after the 2,000 person event. He says she bore down immediately on what she figured he was most concerned about, reading his shirt and promising to be his champion.

“When I got up there, she said that she is going to work on getting rid of student loan debt. I was wearing a shirt that had her picture on it and it says, ‘Hello, do you have a moment to talk about student loan debt cancellation?’” says Mr Eliff, a 31-year-old law enforcement official with more than $70,000 (£57,000) in student loan debt.

After nine months of campaigning, Ms Warren now finds herself as a top contender for the Democratic nomination, and has begun to see her name on top of even Joe Biden’s in polls from across the country.

She’s the first Democrat so far to break that ceiling, and the rise in political fortunes for the 70-year-old has been made possible at least in part by moments just like the one with Mr Eliff. The 31-year-old is among the thousands of people to have taken a selfie with the senator this year, and says that the candidate’s personal approach has all but guaranteed he will be caucusing for her come February.

“The fact that she takes the time to meet with everyone tells me a lot about her. I think she cares about people. And I think people like that. Iowans appreciate the personal touch,” he says. “That fact, that she waits and meets everyone, is another reason among many I endorsed her early and support her and will be caucusing for her.”

For political strategists and experts, Ms Warren’s pioneering of the so-called “selfie line” is a genius move that has helped accomplish a few different goals.

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For one, the selfie lines – which Ms Warren will stick out for hours, making sure every last person who wants one will get their photo with her – allow her to make a personal connection directly with voters. They also show her stamina: what unhealthy person is able to stand for hours greeting strangers day in and day out?

But they also give Ms Warren, who makes the time for the photo lines by refusing the time-suck of big fundraisers with millionaires, the chance to wade in directly with her would-be constituents – who then help out by posting those same selfies all across the internet.

“In many ways, selfies on Instagram have become the new yard signs. Where people see the candidate out from behind the curtain, and see that their friend or their neighbour or their family member is promoting them,” says Jesse Ferguson, the former deputy national press secretary for Hillary Clinton’s 2016 campaign.

“It’s powerful,” he continues, noting that, unlike physical yard signs, selfies can pop up anywhere in your “digital neighbourhood” – not just on the drive to the polls.

And, in an age when earning a viral moment can make or break a campaign, Ms Warren’s approach can make the anonymised experience of the internet somewhat personal, too.

“Yes, many candidates have ‘viral moments’ but Warren may be one step ahead with her person-to-person strategy because it allows both the voter and Warren to have the viral moment together, hundreds at a time. Then those pics are shared across social networks and followers see the pics with zero mention of ‘sponsored content’. A truly organic strategy,” says Cartney McCracken, a Democratic strategist and partner at the firm Control Point Group.

Of course, Ms Warren can point to more than just a well-run selfie operation for her success. From the get-go, she’s cultivated a remarkably consistent political brand, releasing policy proposal after policy proposal to support a central promise she has made on the campaign: she sees the corruption permeating Washington politics, and she has a plan to fix all the problems that stem from that rot.

The former teacher-turned-bankruptcy lawyer has a personal story to tell, too. She pulls her audience in with a relatable narrative, one in which she describes her life story – a success story that has her starting in Oklahoma as the daughter of working-class parents, before making her way through public universities and law school. It’s a story that includes humour, failure and, ultimately, hope.

All of that has culminated in weeks of good headlines, and a growing sense of fear on Wall Street and in Silicon Valley.

“Warren passes Biden in new national poll,” reads one headline in Politico from late September. “Mark Zuckerberg says Elizabeth Warren’s policies are an ‘existential’ threat in leaked Facebook audio,” reads another headline, in The Independent. “Wall Street Democratic donors warn the party: We’ll sit out, or back Trump, if you nominate Elizabeth Warren,” reads one CNBC headline.

Elizabeth Warren at Washington Square Park

“She’s firing on all cylinders when it comes to policy, she’s doing well with fundraising, drawing large crowds and favourable press. But there’s still a long way between now and the caucuses in Iowa,” says Jim Manley, a longtime Democratic operative who previously worked for former Senate majority leader Harry Reid, just before Ms Warren’s campaign announced a $24.6m fundraising haul for the third quarter.

At the largest of those events Mr Manley mentioned, around 20,000 people crowded into New York City’s Washington Square Park. Afterwards, a line formed in the park, and Ms Warren took selfies for nearly four hours.

Caroline Morganti, a 25-year-old software engineer, said she waited for two and a half hours for her moment to see Ms Warren – and saw just one person leave the line during that time.

And Ms Morganti says she is far from ruling out a future President Warren, even at such an early stage in the election when anything could happen.