During her nascent presidential campaign, Hillary Clinton has called for expanded regulation of the financial system, slammed wealth disparity and pushed for tougher punishment on individual rule breakers.

Employees of five financial firms— Citigroup , Goldman Sachs , JPMorgan Chase , Morgan Stanley and Bank of America Merrill Lynch —gave about $290,000 to Clinton's campaign committee through June 30, according to a MapLight analysis of Federal Election Commission data. While it makes up less than 1 percent of the roughly $47 million raised by Clinton's committee this cycle, it follows a precedent set in her 2008 presidential campaign, when the firms' employees were among her biggest donors.

All of that rhetoric has mattered little to Wall Street. Already among the biggest donors to Clinton's political career, employees of some megabanks have funneled big money into her bid for the 2016 nomination.

The pace of Clinton's Wall Street funding, which does not yet include expenditures from political action committees linked to the firms, will likely increase as her campaign continues, Corrado said. Clinton declared her candidacy in April, and the recently released campaign finance data go through the end of June.

"With the direction of Obama economic policy and anti-Wall Street rhetoric seen on the Democratic side, one wouldn't be surprised to see less support from Wall Street," said Anthony Corrado, a professor of government at Colby College who studies campaign finance. "Even so, she continues to have strong support within the financial community."

The cash flow may not make Clinton's policies any easier on banks. But it illustrates the strong support the Democratic front runner maintains with the financial industry even as it has shied away from the party in recent years.

When Clinton and President Barack Obama competed for the Democratic nomination in 2008, both received major Wall Street backing. Those five firms all ranked among the top 20 contributors to Clinton's 2008 campaign based on individual employee and PAC donations, amassing more than $1.8 million among them, according to data compiled by the Center for Responsive Politics. JPMorgan, Goldman and Citi were among her top five donors.

After the Democratic-led passage of the Dodd-Frank Act five years ago and the party ramping up its anti-Wall Street rhetoric, the financial industry's funding to Democrats fell off, Corrado said. Take Obama, who garnered more than $16 million from the securities and investment industry in 2008 but less than $7 million in 2012, according to the Center for Responsive Politics.

Despite the shift, Clinton still attracts Wall Street money. Because she was a New York senator, she maintains an "institutional connection" to the financial industry, said Lisa Gilbert, director of the Congress Watch division at Public Citizen.

Clinton acknowledged that relationship in a speech last week, giving a nod to the what she deemed the financial industry's positive role in the economy.

"As a former senator from New York, I know firsthand the role that Wall Street can and should play in our economy," Clinton said, "helping Main Street grow and prosper and boosting new companies that make America more competitive globally. But, as we all know, in the years before the crash, financial firms piled risk upon risk. And regulators in Washington either couldn't or wouldn't keep up."

Donors also, logically, like to bet on candidates with the best chance of reaching the White House, Corrado and Gilbert said. Though the gap has closed in recent weeks, Clinton holds a cushion over Vermont Sen. Bernie Sanders, her closest competitor in the Democratic primary and one of the most unapologetic Wall Street critics in Washington.

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Sanders' total contributions from employees of Wall Street firms came in at about $6,000, according to MapLight.

The disparity in donations from the financial industry opens Clinton to criticism from Sanders and the staunch left wing of her party, Gilbert said. Still, Gilbert noted that Clinton should not have to be "beholden to those that helped financially" if she took the White House and pushed policy that could anger Wall Street.

Clinton's campaign played down possible backlash from large Wall Street contributions. It set a maximum campaign committee donation of $2,700 and collected its roughly $47 million haul from more than 250,000 individual donors.

"Hillary Clinton is committed to making sure we have an economy that works for all Americans and not just those at the top. That's why she believes that the measure of our success must be defined by how much incomes rise for hard-working families, not just CEO's and money managers. Regardless of the size of their donation, the people who support Hillary's campaign know that's what she's fighting for," said Josh Schwerin, a spokesman for the Clinton campaign.

He added that most of Clinton's contributions came from small donors, as 94 percent of donations amounted to less than $250.