The first day of the Democratic National Convention opened on a jarring, discordant note, as Bernie Sanders supporters in the Wells Fargo Center began booing every mention of Hillary Clinton’s name.

The agitation eventually died down, but it posed an intriguing possibility: Might the Sanders movement outlast his campaign and become a permanent thorn in Hillary Clinton and leading Democrats’ sides?

That is, could it end up as something like the Tea Party — which transformed much of the GOP’s agenda, forced out some of its key leaders, and utterly discredited the party's establishment in the eyes of many of its voters?

What's clear is that the Democratic Party is not too far from a total Tea-Party style takeover. If IF Sanders wing can bring over black D's — Christopher Hayes (@chrislhayes) July 25, 2016

In some respects, the comparison between these Sanders supporters and the Tea Party is overstated. No one knows whether the Sanders movement will manage to live on once the senator’s presidential campaign no longer exists to give it a unifying purpose.

But in one crucial aspect, the comparison could be quite apt. The Tea Party was motivated partly by a deep and growing frustration with the way things are going in this country, and a sense that the party establishments weren’t up to the task of fixing it.

That’s how many Sanders supporters feel, too. And despite the happy talk from President Barack Obama and the Clinton campaign about how great everything’s going, that’s how many Sanders supporters still feel.

The real risk for the Democratic Party is that these Bernie backers and other rank-and-file Democrats could move from feeling frustrated about the system as a whole, to strongly believing that Democratic elites are the problem and should be ousted.

That’s what happened with the Tea Party and Republican elites, and that’s what could well happen to President Hillary Clinton, should she win this fall.

Sanders backers are deeply concerned with the state of the country

Surveys of the growing policy similarities between Hillary Clinton and Bernie Sanders — the public option, free college, and the platform they negotiated — could fool observers into thinking the Democratic Party has found a happy consensus.

Don't believe it. The real divide here isn’t mainly about policy white papers. It’s over what ails America in the 21st century, and what kinds of political behaviors are acceptable.

I wrote about this when I interviewed Sanders supporters in Iowa back in January. They felt something was badly wrong with America — citing skyrocketing inequality, stagnant wages, and the corrupt influence of corporations and the wealthy — and argued that major change was necessary.

"We've really drifted into the government being for the people with the big money rather than being for and of the people," said Ron Yarnell of Johnston. "The government is so entrenched in corporate policy, so entrenched in enriching corporations," said April Burch of Boone.

Essentially, these Sanders backers agreed with the vision Elizabeth Warren laid out during her speech Monday, that powerful elites constantly rig the system for their own benefit. "Americans bust their tails, some working two or three jobs, but wages stay flat," Warren said. "There’s lots of wealth in America, but it isn’t trickling down to hard-working families like yours." She added, with a flourish: "This. Is. Not. Right!"

And if these really are such desperate times for our economy and political system, then doesn’t that suggest we need desperate measures? Wouldn’t we need something bigger — a political revolution, a major shakeup — to meet this challenge, rather than politics as usual?

The Democratic Party really does court corporations and the wealthy

Furthermore, the core critique Sanders backers have of mainstream Democrats has a good deal of truth to it. While many leading Democrats often battle corporate interests, others do frequently modify or abandon their liberal principles for the benefit of corporations and wealthy donors.

Hillary Clinton and her husband have been enthusiastic participants in the big dollar fundraising culture (as has Obama, though he gets less grief for it). Many political appointees or other major figures in both the Bill Clinton and Obama administrations have been close to industry. And others cashed out afterward for hefty private sector salaries — for instance, budget director Peter Orszag went to Citigroup, and campaign manager David Plouffe went to Uber.

The reality is the Democratic Party relies on raising money from wealthy individuals. Their leaders justify it by saying there really is no alternative fundraising model that could let a major political party compete with the Republicans’ big dollars. But the downside is that, of course, there is this undeniable element of corruption.

Bernie Sanders’s stunning small donor fundraising may seem at first to offer a glimmer of hope for the future, but it’s also a model we’ve seen before on both the left and the right. It’s a model that works well for particular types of candidates — charismatic and unusual figures who can capture the attention of the national grassroots, like Michele Bachmann, Allen West, and Alan Grayson.

The problem is that those sorts of candidates don’t turn up very often, and it’s not clear small donors’ attention can be captured by very many of them. So unless Sanders can scale up his fundraising machine to help candidates who aren’t as personally inspiring, the primary fundraising model of the Democratic Party isn’t going to change.

And left-leaning voters who see that fundraising model as the central corrupting force in American politics will keep getting angrier and more disenchanted with the party.

Still, the best way for progressives to enact their preferred policies is for Democrats to win more elections

So yes, the Democratic Party remains somewhat beholden to corporate cash and big money, and progressives should fight to hold their feet to the fire.

But if Sanders supporters think Democratic fecklessness is the main reason they're not getting the change they want, they’re missing the forest for the trees.

The biggest reason we’re not living in a paradise filled with bold progressive governance really is a simple one: It’s because the Republican Party has controlled either the presidency or a house of Congress for all but two of the past 22 years. And any judgment about how Democratic leaders are "sellouts" really has to reckon with this fact.

Yes, the Democratic Party could push for more liberal policies. But discussions about, say, whether the party should more boldly fight for single-payer health care, a carbon tax, or a tougher Wall Street reform bill are largely academic in a political system where a deeply conservative Republican Party controls Congress. Even in 2009 and 2010, Democrats' strongest position in years, the 60th Senate vote and thus the veto point for change was, at various points, either the very conservative Democrat Ben Nelson or the moderate Republican Olympia Snowe.

Tea Party supporters have had this forest-trees problem too: They’ve assigned far too much proportional blame for their disappointments on Republican leaders who they deem sellouts. Yet apart from the issue of immigration policy (a topic on which GOP elites truly were trying to sell out their base), the main reason the Tea Party can’t get its way is that Barack Obama has been president for the movement’s entire existence.

For both the Tea Party and Sanders fans, the solution to many of their gripes is conceptually quite simple: They just have to win more elections.

The best path forward for the left, at the national level, is to organize in House districts. The House of Representatives has been the most consistent chokepoint for progressive proposals in recent years. Sanders supporters who want change should recruit strong challengers to seats held by Republicans nationwide, and try their damnedest to organize and solve the Democrats’ persistent turnout problem in off-year elections.

But this will take years of hard work, investment, and frustration — and, perhaps, compromise to win over voters in those Republican-controlled areas.

The Tea Party's best path forward was to work hard to win the presidency in 2016, which could have ushered in a new age of conservative change. But instead, the movement took its eye off the ball. Supporters became so deeply frustrated at failing to get what they wanted soon enough that they ended up turning their rage against Republican establishment politicians like Eric Cantor, forcing counterproductive policy fights like the 2013 government shutdown — and utterly discrediting the leadership of the party, which helped pave the way for the rise of Donald Trump. (If Republican leaders hadn't been so discredited in the eyes of their voters, we could be living in a very different world.)

The question for Democrats is whether Sanders supporters’ inevitable frustration will end up being turned against Republicans who control the House, or against a Hillary Clinton administration and congressional Democrats who they deem insufficiently pure.

So far, the personal charisma and popularity of Barack Obama have prevented such a critique from catching on among rank-and-file Democrats. But Sanders supporters (and Sanders himself) have had no such hesitations in applying that critique to Hillary Clinton — wife of infamous 1990s deregulator Bill Clinton, giver of Goldman Sachs speeches.

And as Hayes suggests, if black voters or Hispanic voters end up becoming disenchanted with Clinton generally for whatever reason, an anti-establishment coalition could become incredibly formidable in Democratic primary politics.

The Democratic Party already is moving left, with unclear implications for its electoral fortunes

Amidst the dissatisfaction with the current state of the Democratic Party, we shouldn’t obscure the fact that the party really has been moving further to the left, on economic and domestic issues at least.

Indeed, this leftward movement puts the party in a bit of a double bind. Because Democrats have lately performed absolutely dismally in midterm elections and in the states, and a national move left may well hurt them even more in those contests.

Part of this shift is that, in recent years, the party has wholeheartedly embraced its identity as the party of marginalized demographic groups — black voters, Hispanic voters, unauthorized immigrants, women seeking equal pay, and LGBTQ rights supporters.

Democrats used to be terrified about moving too far away from the white male mainstream, but they now seem to believe that in a changing America, diversity is the mainstream. As Dara Lind put it, this shift is "both meaningful to party activists and a painless concession to its power brokers: a sweet spot for party unity."

Yet much of the party has moved on economic issues too:

Rank-and-file Democrats have rejected a Democratic president’s major trade deal, which now may be dead.

Talk of a grand bargain on entitlement reform and the need for deficit reduction, common among Democrats just five years ago, has vanished.

The call for "free college" has moved from the party’s fringe to its mainstream.

And the Clinton campaign is openly bragging that they’ve adopted "the most progressive platform in party history" — a platform that, don’t forget, came out of negotiations with a democratic socialist (a label long thought anathema in US politics).

Much of this would have been utterly unthinkable in the 1990s and 2000s, when embattled Democrats dropped or downplayed their liberal leanings and proposals for big new spending programs.

Still, Democrats were so hesitant back then for a reason — they were afraid the public wouldn’t support those policies, and that they'd lose their elections if they went too far left.

And make no mistake, the electoral implications of the party’s recent leftward shift aren’t yet clear. Yes, the country is getting more diverse and that bodes in Democrats’ favor. But there still are a whole lot of white voters out there, and they could trend more Republican. Yes, a more forceful critique of inequality could energize more voters in the midterms. But remember that there was quite a backlash to Obama’s liberal policies in the 2010 midterms.

So the Democratic establishment will face an awkward challenge in years to come. They’ll have to satisfy an increasingly energized left, while also struggling to expand their appeal in the state and off-year elections where they’ve done so poorly of late.

Furthermore, should Clinton win in 2016 and, as expected, be faced with a Republican-controlled House of Representatives, gridlock will likely ensue, and the intense frustration of Sanders supporters and other left-leaning Democrats will only deepen.

So if the party’s leaders want to keep their jobs, they'll then have to figure out how to convince their own voters that they’re not the problem.