“Dean pulls away in Dem race” was the headline after a national poll put the former Vermont governor safely ahead of all challengers just five weeks before Iowans would cast the first votes for the 2004 Democratic presidential primary. Thirteen points back and tied for second and third were U.S. Senator Joe Lieberman and retired General Wesley Clark. And in sixth place, weighing in at a “when is he going to drop out of the race” 4 percent, sat Massachusetts Senator John Kerry—the eventual nominee.

Not only did Kerry vault from sixth to first, but the seventh-place finisher in that December poll, North Carolina Senator John Edwards, would finish second and join Kerry on the ticket.

Most pundits have whittled the 2020 Democratic primary field down to three or four true contenders and a slew of also-rans. Our review of past Democratic presidential primaries tells us there is more to this race than meets the eye, and those who seem to be languishing—like John Kerry in the 2004 race—have a lot more life than they’re given credit for.

We looked at all 10 contested Democratic presidential primaries dating back to 1972, the year our modern primary system began. To look at past polling and candidates’ status in the horse race, we relied on the excellent work of Geoffrey Skelley, writing for the 538 blog, where he averaged all available public opinion polling for the six months preceding the Iowa caucuses. And we leaned on our own experience as observers and sometime participants for various candidates. Here are the four key lessons we learned.

First, there’s good news for Joe Biden and Elizabeth Warren. Frontrunners win. There’s also bad news. They win only 30 percent of the time. In just three of 10 contested Democratic primaries, the leader in the polls in the months preceding the Iowa caucuses ended up winning the nomination: Walter Mondale in 1984, Al Gore in 2000, and Hillary Clinton in 2016.

Second, forget the notion of a “weak” versus a “strong” frontrunner. Those terms are meaningless. By historic standards, Biden is a strong frontrunner. Besides his status as a former vice president, he has genuine support in the African-American community, which represents about a quarter of the primary electorate. Ideologically, he is in tune with the Democratic electorate, which skews more moderate than the activists on Twitter. And co-frontrunner Warren draws enormous crowds, performs well on the debate stage, and has a policy plan for most everything, which appeals to the wonky nature of many primary voters.

But as Warren learned in the most recent debate, frontrunners face scrutiny and pressure that no other candidate in the race has to endure. Ed Muskie may or may not have brushed a tear away in the driving snow as he defended his wife against a vicious campaign attack leveled only because he was the 1972 frontrunner.

Ted Kennedy muffed an interview with CBS anchor Roger Mudd that would have been a shrug of the shoulders, not a body blow to the campaign, had he not been the favorite to unseat President Jimmy Carter in the 1980 race. We would not know the name Donna Rice if Gary Hart wasn’t the frontrunner for 1988 and being tailed by reporters. And Howard Dean’s scream would not even be a footnote in campaign history if he wasn’t the presumed leader heading into the 2004 Iowa caucuses.

That’s why Donald Trump risked the guillotine to demand the Ukrainian president investigate Biden and not Andrew Yang. Biden is a frontrunner. Gravity doesn’t drag frontrunners down; the enormous burden that comes from having a target on one’s back does.

Third, when the frontrunner fades, the race is truly a scramble. You might think that when that happens, the person in second place benefits, but in fact, that is rare. Just two of 10 eventual primary winners occupied the No. 2 spot in national polling in the months leading up to the Iowa caucus: Barack Obama in 2008 and Jimmy Carter in 1980. And Jimmy Carter was the sitting president at the time.

“ Mayor Pete Buttigieg could be the Jimmy Carter of this race – the fresh face, untainted by Washington. ”

In fact, there were as many Democratic primary winners who jumped from fifth place or worse to first as those who went post to post. Eventual winner George McGovern was in fifth place in the 1972 race. Jimmy Carter was in 10th place in 1976. John Kerry was in sixth place leading up to the 2004 nomination.

And fourth, in most primaries, a candidate beloved by the far left appears to be winning—only for that moment to pass. At one point, Ted Kennedy, Jesse Jackson, and Howard Dean all led their respective primaries, and none came close to winning. George McGovern managed to win from the left in 1972, but he actually received fewer popular votes in the primary than Hubert Humphrey.

Walter Mondale was loved by the left in 1984, but as a former vice president he was also the establishment candidate. Vermont Senator Bernie Sanders may be reprising that role in this race as his poll numbers appear to be slipping at least in some surveys and he’s replaced key staff in Iowa and New Hampshire.

What does it all mean? If you like a candidate who is mired in the single digits, don’t give up. All of this uncertainty means there’s space for others. Mayor Pete Buttigieg could be the Jimmy Carter of this race—the fresh face, untainted by Washington, who appeals to young voters and a broad array of others across the ideological spectrum. Senator Kamala Harris had a lousy summer, but so did Barack Obama in 2007 before he took off in the fall.

Senator Amy Klobuchar, a moderate, makes a compelling argument that she is electable against Trump, is consistently strong on the debate stage, is great on television, and has an added advantage of being from a state neighboring Iowa. Senator Michael Bennet is the futurist, in the mold of a young Gary Hart in 1984 who went from 3 percent to almost swiping the election from Mondale as the candidate willing to speak hard truths. Cory Booker hasn’t budged in the polls, but he keeps winning debates. And former Rep. Beto O’Rourke, after a rocky first debate, is seeking a second wind around the issue of guns.

If you’re reading this article and have made it all the way to the bottom, congratulations—you’re among a handful of Democratic voters following this race obsessively. But there are about 30 million others who are just beginning to tune in. They will ultimately decide who our nominee is. In 2018, they overwhelmingly chose mainstream Democrats in House, Senate, and gubernatorial primaries. Those mainstream candidates flipped the House from red to blue, turned seven governors’ mansions, and kept Senate losses to a minimum in the face of a tough map. They could very easily run that playbook again.

So don’t give up fans of also-rans. You still have a chance. And so do a half-dozen others.

Jon Cowan is president and Jim Kessler is executive vice president for policy at Third Way, a center-left think tank in Washington, D.C.