Hillary Clinton’s ties to the financial industry have come under renewed scrutiny, after she faced tough questions about her paid speeches to Wall Street at a televised “town hall” event in New Hampshire.

Asked by CNN host Anderson Cooper whether her acceptance of $675,000 (£463,000) in speaking fees from Goldman Sachs amounted to “a bad error in judgement, the former US Secretary of State , who took the payment for three speeches to the Wall Street investment firm in 2013, argued that she had “made speeches to lots of groups”.

Pressed on the size of the fee, Ms Clinton responded: “That’s what they offered. Every Secretary of State I know has done that.”

Still the frontrunner for the Democratic presidential nomination, Ms Clinton won a victory over Bernie Sanders by the narrowest of margins in Monday’s Iowa caucuses.

She remains well ahead in national polls, but trails behind Mr Sanders in New Hampshire, which holds its primary on Tuesday.

The gloves have come off as both prepare for their next contest, with Mr Sanders persistently questioning Ms Clinton’s progressive credentials.

“I don’t know any progressive who has a super PAC that takes $15m (£10.2m) from Wall Street,” the Vermont senator said at the same meeting late on Wednesday.

“I’m amused that Senator Sanders has set himself up as the gatekeeper of who gets to be a progressive,” Ms Clinton responded. Under Mr Sanders definition, she said, “Barack Obama would not be a progressive, Joe Biden would not be a progressive.”

Mr Sanders has made hay with his rival’s Wall Street speaking fees during previous encounters.

Hillary Clinton in quotes Show all 11 1 /11 Hillary Clinton in quotes Hillary Clinton in quotes Hillary Clinton After losing the 2016 election: 'To all of the little girls who are watching this, never doubt that you are valuable and powerful and deserving of every chance and opportunity in the world to pursue and achieve your own dreams.' Getty Hillary Clinton in quotes Hillary Clinton On running for President in 2016: 'I'm going to decide when it feels right for me to decide. ... certainly not before then [the end of 2014].' AP Hillary Clinton in quotes Hillary Clinton On the Monica Lewinsky affair: 'It’s liberating to be able to reach the point in your life where you feel you can forgive. Everybody feels they have been trespassed upon and nearly everybody has trespassed on somebody else, maybe not intentionally.' Hillary Clinton in quotes Hillary Clinton On news and hair: 'If I want to knock a story off the front page, I just change my hairstyle.' Getty Images Hillary Clinton in quotes Hillary Clinton On being asked which fashion designers she preferred: 'Would you ever ask a man that question?' Getty Images Hillary Clinton in quotes Hillary Clinton On equality: 'Well I'm very conscious of how important it is for us to shatter that glass ceiling in my country. A country that has done so much for so many women and really has set the standard for women's rights and responsibilities, and I do want to see that glass ceiling shattered.' Getty Images Hillary Clinton in quotes Hillary Clinton On not winning in 2008: 'I think because I really didn't have a good strategy for my campaign. I didn't plan it the right way. ... As a candidate who was already so well known ... I don't think I ever said, 'Yes, you may have known me for eight years, but I don't take anything for granted. I have to earn your support.' Getty Images Hillary Clinton in quotes Hillary Clinton On self-confidence 'You have to be true to yourself. You have to be enough in touch with who you are and what you want, how you want to live and what's important to you, to make your decisions based on that. Sometimes that's very difficult.' AP Hillary Clinton in quotes Hillary Clinton On 9/11: 'Every nation has to either be with us, or against us. Those who harbor terrorists, or who finance them, are going to pay a price.' Getty Images Hillary Clinton in quotes Hillary Clinton On women around the world: 'If women are healthy and educated, their families will flourish. If women are free from violence, their families will flourish. If women have a chance to work and earn as full and equal partners in society, their families will flourish. And when families flourish, communities and nations will flourish.' Getty Images Hillary Clinton in quotes Hillary Clinton On her political life: ‘I suppose I could have stayed home and baked cookies and had teas, but what I decided to do was to fulfill my profession which I entered before my husband was in public life.’ Getty Images

According to a New York Times calculation, Ms Clinton and her husband, former President Bill Clinton, have earned more than $125m (£85.7m) from speeches since he left office and the White House in 2001.

Ms Clinton has made speaking appearances at a series of major financial firms including Morgan Stanley and Deutsche Bank, while Mr Clinton was paid $200,000 (£137,000) for giving a speech to Goldman Sachs in 2013, the same year his wife gave three.

Yet Ms Clinton challenged those sceptical of her Wall Street links to “name anything they’ve influenced me on”, adding: “I’m going after them. I’m going to jail them if they should be jailed. I’m going to break them up. They’re not giving me very much money now, I can tell you that much.”

In fact, Ms Clinton has now received more cumulative support for her campaigns from the financial sector than her husband did over his own electoral career. More than 10 per cent of contributions to her 2016 campaign have come from financial industry donors, the Washington Post reported.

The former Secretary of State has also received an indirect – and unwanted – endorsement from the CEO of Goldman Sachs. Appearing on CNBC this week, Lloyd Blankfein lamented Mr Sanders’ attacks on the “billionaire class”, saying the Senator’s rise “has the potential to be a dangerous moment.”