Hillary Clinton was plagued by her perceived coziness to Wall Street in Election 2016. As Democrats look ahead to 2018 and 2020, they have important questions to answer on how they interact with big finance and corporate America, especially when it comes to fundraising.

Progressives and moderates have engaged in an ongoing push-and-pull over the direction of the party since the last election, a major element of which is a tussle over their approach to campaign donations. While talking tough on Wall Street is a winner politically, taking money from Wall Street to run campaigns is another story.

Bernie Sanders during the 2016 presidential primary raised more than $200 million, largely through small-dollar online donations he often boasted averaged $27 each. Unlike Clinton, who had two super PACs behind her (as well as grassroots donors), he refused super PAC backing and instead depended largely on grassroots efforts online.

"Bernie might have raised $1 billion online if he was the party's nominee," said Kenneth Pennington, who directed digital operations for the Sanders campaign.

But it is unclear whether Sanders is an exception or a new rule. Pennington said he believes Democrats can raise enough to supplant big-money donors entirely, but the party has not yet tested the case, and doing so could be risky.

"The reality may be that if Democrats unilaterally disarmed themselves of super PACs and 501c4s over night, the Republicans might just crush them," he said. "Is that good for the American people? No. But, is there a way for the Democratic Party to earn the trust of working people and small-dollar donors in order to buck these wealthy elites and win real reform over time? I believe so."

Progressives have seen a burst in enthusiasm since Donald Trump's election to the White House. Millions of people took part in the Women's March the day after his inauguration, and groups encouraging progressives to run for office have popped up across the country. Democrats have racked up wins in state elections, though they have yet to score a victory in special Congressional elections this year.

"Trump's election helped folks really take a hard look at the nature of politicians and folks running for office in this country," said Carolyn Fiddler, senior communications adviser at progressive platform Daily Kos.

But liberal enthusiasm hasn't translated symmetrically to dollars. The Democratic National Committee is lagging behind its Republican counterpart in fundraising this year, raising $38 million compared to the GOP's $75 million in the first half of 2017. And it is falling short on the small-dollar donations that fueled Sanders.

Michael Whitney, who managed the Sanders campaign's digital fundraising in 2016, in an August op-ed explained his thoughts on why: Democrats aren't inspiring voters in the right ways.

"People are motivated to act when they feel like part of something larger than themselves -- and when they understand that their participation in that larger something makes a real difference," he wrote. "The Democratic Party's woes are basic symptoms of the failure to understand that immutable reality."

A Washington Post-ABC News poll in April found that two-thirds of Americans think the Democratic Party is out of touch with the country, more than said the same about Republicans. Moreover, more than four in 10 Democrats said their party was out of touch.

Whether that is a perceived or real distance is up for debate.

Many Democratic policies -- higher minimum wage, increased access to healthcare, infrastructure spending -- are designed to boost workers and the middle class. Democrats struggled to connect with those groups during the election, with Clinton losing blue-collar voters in Wisconsin, Michigan and Pennsylvania who have in other recent cycles have been loyal to Dems.

Taking a tougher tack on Wall Street and corporate America, as progressive figures such as Sanders and Senator Elizabeth Warren (D-MA) have done, may be a way for Dems to reconnect with American voters and, in turn, up grassroots donations.

Over the summer party leaders laid out a platform targeting megamergers, and anti-monopoly candidates are cropping up in elections across the country. Senator Amy Klobuchar (D-MN) has introduced legislation to modernize U.S. antitrust laws. Representative Maxine Waters (D-CA) has introduced a bill to shut down "abusive megabanks."

Recent major missteps by companies such as Equifax (EFX) - Get Report , Facebook (FB) - Get Report and Wells Fargo (WFC) - Get Report have given Democrats plenty of talking points.

"It's good politics to take a touch stance on Wall Street," said David Gold, director of research at public affairs firm Global Strategy Group. "All the polling I've seen is quite clear that voters want to see corporate America held more accountable and have millionaires and corporations pay more in taxes."

Being a vocal opponent of business could put a target on some candidates' backs from corporate special interests, but it could also appeal to voters -- and therefore inspire them to open up their wallets. "Voters are going to think you're doing something right and may even be more eager to chip in," Gold said.

Of course, just because Democrats talk tough on corporations doesn't mean those same corporations will stop giving. President Barack Obama brought in millions of dollars from Wall Street even after he signed sweeping regulatory legislation Dodd-Frank. Clinton often points out there is no evidence donations to her campaign never affected her positions or votes.

But the optics of taking money from big business, whether it has influence or not, are not great.

"When voters see corporate special interests having an outsized influence in our politics, they're going to blame politicians for enabling them more than they're going to blame corporations for trying to make money," Gold said. "That's why it's so important for candidates to show that they understand voters' frustrations with the influence of money in politics. Voters know that politicians have to be the ones that end this cycle, because corporate America isn't going to police itself."

Democrats are increasing their efforts on grassroots fundraising. ActBlue, the progressive fundraising platform that fueled Sanders' online efforts, has helped left-leaning candidates and causes raise $1.8 billion online since 2004. Democrat Jon Ossoff raised millions of dollars in Georgia's special election to replace the House seat vacated by Tom Price.

Representative Ro Khanna (D-CA)in July announced the "No PAC Caucus," a group that rejects lobbyist and political action committee contributions. Beto O'Rourke (D-TX) and Jared Polis (D-CO) are also members.

"The Democratic Party should shift its reliance away from donors writing big checks toward small-dollar online fundraising from tens of millions of people," Pennington said. "Embracing small-dollar fundraising will increase trust in the party and inevitably realign the party's policy priorities to be in lock step with working families rather than wealthy donors."

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Editors' pick: Originally published Oct. 5.