“Objects in your rearview mirror are closer than they appear.”

That was what Kurt Meyer, the Democratic Party chairman for Worth County, Iowa, reportedly told Hillary Clinton’s political director after more people showed up to Bernie Sanders’s event in the small town of Kensett on Saturday night than the town’s overall population. Earlier in the week, Sanders drew 700 people to a rally in Davenport. As the New York Times noted yesterday, that’s the largest rally any candidate has held in the state so far this election cycle, and puts Martin O’Malley’s 50-person event in the same town on Saturday to shame.

As Iowa State political science professor Steffen Schmidt tweeted from a Sanders campaign event at a brewery in Ames, “Hillary should worry:”

Bernie Sanders in Ames Iowa today. HUGE overflow crowd at brew pub. Hillary should worry. pic.twitter.com/GtjCicBxSA — Steffen Schmidt (@DrPolitics) May 30, 2015

Since announcing his candidacy, Sanders has shown signs of life in what was originally thought to be a one-horse race for the Democratic nomination. A recent Quinnipiac poll had him pulling fifteen percent of the Democratic electorate. For perspective, that’s higher than any candidate earns in RealClearPolitics’s polling average for the Republican nomination (Jeb Bush is in the lead with 14.8% of the vote).

As Georgetown professor Michael Eric Dyson told a roundtable on ABC’s This Week yesterday, “Bernie Sanders is proving there is a little bit of socialist in a lot of people on the left.”

This shouldn’t come as a surprise. Sanders is saying things that liberals have been dying to inject into presidential politics for a very long time. As Matt Bruenig pointed out, writing for Demos, when Sanders told John Harwood that, “The whole size of the economy and the GDP doesn’t matter if people continue to work longer hours for low wages and you have 45 million people living in poverty…You don’t necessarily need a choice of 23 underarm spray deodorants or of 18 different pairs of sneakers when children are hungry in this country,” he was widely dismissed by mainstream journalists when in fact this was one of the most substantive debates currently permeating our political discourse:

Whenever someone argues that we should distribute the national income more evenly so as to reduce poverty and inequality (as Sanders does), the very first thing someone says in response is that doing so will reduce growth and innovation. Sanders is mocking this argument, saying he’d gladly cut poverty and inequality even if it meant a reduction in superficial product innovation. If the company that determined there was big money to be made by innovatively telling teen boys that using a certain brand of deodorant would cause attractive women to have sex with them decided not to go through with creating Axe because taxes were too high, Bernie is saying he is OK with that. You might have less brands to choose from on the deodorant aisle, but on the plus side kids will get to eat.

That’s a much more serious challenge to economic inequality than any Republican or Third Way Democrat such as Clinton could ever dream of. It’s a challenge that makes sense to the millions of Americans who in the back of their minds understand our current system forces too many to choose between food and heat, while allowing them to also choose between Old Spice and Dove.

It’s a conversation that any other presidential contender would be unwilling to make, even if they know it makes sense, because their money would dry up and they’d get called a socialist on a Sunday news show. Bernie Sanders is not weighed down by any of that, nor is he weighed down by any of the other obligatory campaign scripts that are already making the media — to say nothing of the voters — frustrated with Clinton. As Jeb Lund wrote in The Guardian:

Bernie is not polished, because Bernie does not give a fuck. Bernie has shit to do, which is ostensibly why he was elected. For his pre-announcement – days ago – he walked outside the US capitol, took questions for ten minutes, then walked back inside to resume being a Senator. This approach is or is not a problem, depending on how hypocritical you think people are. Few people have spent their lives lamenting that politicians were insufficiently blow-dried. (NO. Make the hairTRUMPIER.) Most bemoan the plasticity of candidates and the lack of real priorities signified by omnipresent flag pins and a slightly different red tie than the guy next to him… …Bernie is not rich and he does not spend his time figuring out how to convert political problems into wealth opportunities for people who are already rich. Many people depict this as a liability – mostly rich people who consider choosing the government to be exclusively their purview, and the sorts of people who become rich by overcharging rich people for campaign ads, advice and strategy. Both of these groups will tell you that Bernie has no chance, because it is in their bottom-line interests to make demonstrations of a lack of fealty to wealth seem politically anathema.

Bernie Sanders is the kind of politician everyone says they want. And when a politician is transparently genuine, as opposed to transparently fake, voters — surprise! — pay attention. It’s what they’ve asked for in every election since there have been elections, and their request has almost always been ignored.

In Bernie’s case, this transparency is augmented by the fact that — as Lund notes — the voters are way more liberal than either the press or their own representatives believe them to be. So Sanders’s candidacy fills the two biggest voids in the presidential field: that of progressives and that of actual people.

Beyond organic support, Sanders is proving more than capable of running a modern campaign that can raise money and disseminate his message. He’s already Internet famous, winning a Shorty Award in 2012 for best member of Congress on social media, and he’s currently sending the highest-engaging emails of any candidate. His staff, volunteers and voters are excited in the same way that Hillary’s are pragmatic, and the same words could have been written about Barack Obama in 2007.

Sanders’s momentum on the campaign trail over the weekend drowned out Martin O’Malley’s lackluster Baltimore campaign launch that was met with protestors shouting him down over the expansion of the city’s aggressive policing practices. As FiveThirtyEight noted, if there is a serious threat to Hillary Clinton in the primary, it will come from Sanders and not from O’Malley.

Oh, and you probably missed it because it doesn’t matter at all, but Lincoln Chaffee announced over the weekend that he’s going to announce his candidacy (for serious this time) on Wednesday. Again, there isn’t any contrast that any of the other members of the likely Democratic field can draw against Hillary that Sanders isn’t already doing and doing better.

For now, Sanders and Clinton are running a perfectly congenial race. Clinton has operated as if Sanders doesn’t exist; Sanders has pivoted every time he’s pressed to attack Clinton, reframing questions about Clinton’s high speaking fees and moderate policy positions to instead attack Wall Street decadence and pitch his ideas for addressing economic inequality, starting with making public college tuition-free.

It might not take that much of an increase in Sanders’s poll numbers to make all of that change.