frontrunner for the Democratic presidential nomination Hillary Clinton. Picture: Darren McCollester / Getty Images / AFP Source: AFP

What appears to be a mind-numbingly boring graph in fact reveals who’s been funding the federal political careers of Democratic presidential hopefuls Hillary Clinton and Bernie Sanders, and the contrast is striking.

The image, which has been shared more than one million times since it first surfaced on Imgur.com, may also suggest the former Secretary of State’s victory in the Democratic primaries is not such a sure thing.

This version of the graph shows the top 13 donors for each candidate. Source: Supplied

All but two of Clinton’s top 20 donors are large corporations, major banks or law firms, dominated by Citigroup, Goldman Sachs and DLA Piper.

Conversely, all but one of Sanders’ major donors are from labour unions, such as the Machinist/Aerospace Workers Union, Teamsters Union and United Auto Workers.

The donations, which date back to 1989, do not come directly from the organisations themselves but from individual employees or political action committees, or PACs, within the organisations.

News source Digg.com suggests the graphic represents “exactly the type of comparison that Bernie Sanders wants voters to draw between him and Hillary Clinton — portraying him as a candidate backed by individuals and unions and her as a candidate backed by corporate interests”.

Presidential hopeful Hillary Clinton at a Fourth of July parade in New Hampshire last weekend. Picture: AP / Robert F. Bukaty Source: AP

There is also a massive difference in how much each candidate raised: Clinton received more than $US8.39 million from her top 20 contributors alone, while Sanders fetched just $US1.13 million.

Sanders said last month average Americans families made up the backbone of his campaign donors, adding there was a “need to transform our economics and politics so that millionaires and billionaires can’t buy elections”.

An independent Senator for Vermont and a self-professed socialist, the underdog is firming as a major challenger to Clinton and his surge in polls in New Hampshire and Iowa, which Clinton looks likely to lose, suggests he could be giving the Clinton camp a run for its money.

“We are worried about him, sure. He will be a serious force for the campaign, and I don’t think that will diminish,” Jennifer Palmieri, the Clinton campaign’s communications director, told MSNBC overnight.

Democratic presidential candidate Senator Bernie Sanders on the campaign trail. Picture: Michael P. King / AP Source: AP

The donations data has emerged as the disappearing middle class and concern over corporate influence in politics firm as key issues in the 2016 presidential election.

Clinton and Sanders have touted wealth equality as among their core campaign platforms, with both in strong favour of higher taxes for the wealthy and staunchly opposed to the privatisation of social security.

“Never before in the modern history of our country have so few had so much and so many had so little,” Sanders said before confirming his presidential bid last year. “This incredible and obscene level of wealth and income inequality is a grave danger to our economy and our political system.”

Clinton, too, has the rich and powerful in her sights: “The deck is stacked in their favour,” the Democratic frontrunner said in her first week on the campaign trail. “My job is to reshuffle the cards.”

Californian College Republicans protesting against Hillary Clinton's fundraising visit outside the Democratic Party offices in California, where Clinton regularly met with deep-pocketed supporters to amass funds needed to win the White House. Picture: AFP / Mark Ralston Source: AFP

However, while Sanders wants to break the power of the rich upper class, the New York Times reported last year that Clinton was determined to tackle income inequality without alienating businesses or castigating the wealthy.

Figures released last week revealed Clinton has raised $US45 million in political donations towards her primary campaign, which was partly drawn from paid public speeches. Recent figures puts Sanders’ haul at about $US15 million.

Leaked emails from University of Missouri officials, also released last week, revealed Clinton’s representatives were seeking a whopping US$275,000 for the former First Lady to speak at a gala luncheon in Kansas City in February.

Upon learning the fee, the university booked her daughter Chelsea Clinton instead for the bargain price of $US65,000.

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