Ah money. Presidential elections are big business. Clinton's 2008 White House bid raised US$229.4 million ($276.4 million). She was eclipsed by Obama whose take hit a record US$1.073 billion. But since 2010, when the Supreme Court Citizens United v. Federal Election Commission decision allowed individuals, unions and corporations to channel unlimited funds to candidates via super PACS [Political Action Committees], the floodgates have opened.
Beyond a few "guiding principles" super PACS are laxly regulated; money raised and spent must be reported to the FEC, and it is illegal to channel funds into personal use or coordinate super PAC and campaign spending.
Michael Beckel, a reporter with the Centre for Public Integrity, warns super PACs are "an easy tool" to hustle money using someone else's name. One such person appears to be John Gibson, a self-described "billionaire in training" behind the Time for Hillary super PAC. A CPI investigation suggests Gibson is a grifter who as "J.R. Worthington" exploited Clinton's fame for profit. "We have strong evidence to suggest John Gibson was using the alias J.R. Worthington and promising to register a million new voters when the website is little more than an online store," says Beckel.
Gibson is of peripheral concern to Clinton (there is no evidence she knew him or benefited from Time for Hillary), but an evolving Washington DC corruption scandal - revealing the dangers for political candidates on the money trail - may pose a threat.
It involves a DC accountancy firm, Thompson, Cobb, Bazilio & Associates, that US prosecutors call an "assembly line for illegal campaign contributions". This includes off-the-books contributions to various candidates - including almost US$50,000 to Clinton's 2008 campaign. The firm received over US$69 million in US and DC contracts in the last decade.
The man at the centre is the firm's ex-CEO Jeffrey Thompson who is being investigated by a grand jury. Other players include his publicist, Jeanne Clarke Harris, convicted in 2012 for making straw donations from a businessman to Troy White, convicted for failing to declare US$608,750 spent on "street teams" to promote Clinton in Texas.
There is no evidence Clinton - who attended a 2007 fundraiser at Thompson's DC firm - was aware of any wrongdoing and her 2008 team is co-operating with investigators. The danger is that Clinton's enemies - should she run in 2016 - may exploit such murky dealings to smear her.
Tracking dubious money is increasingly a problem in US politics: Clinton had to return US$850,000 in 2008 after two schemes led to the conviction of Norman Hsu and William Danielczyk on campaign finance violations.
"Whenever a campaign has pressure to raise incredible amounts of money, you run the risk for developing associations you didn't know you have," says Bob Biersack, senior fellow with the Centre for Responsive Politics.
The key is due diligence to avoid time bombs that may explode at a crucial moment. "Whenever these allegations surface you have to deal with it. "
Meanwhile, her party's nomination is Clinton's for the asking. A recent CNN/ORC International poll gave her 65 per cent support among Democrats and Independents, with 10 per cent for Vice-President Joe Biden. A super-PAC, Ready for Hillary, had raised US$1.25 million by June's end. Clinton's silence on her intentions has not discouraged growing media speculation on a 2016 run - and what pitfalls lie in wait. Last week the New Yorker, a liberal magazine, asked if a "Hillary Clinton 2016 campaign is a good idea - for the Democratic Party, our collective sanity, even for her?" Would a Clinton campaign derail in a "train wreck".
One potential minefield is the Bill, Hillary and Chelsea Clinton Foundation. Could there be a conflict of interest, with rich donors expecting payback in a Hillary White House?
If she runs there are fears Republicans will resurrect the ghosts of her husband's tumultuous presidency. But would her demographic - youth, women and minorities - care about events that happened in the 1990s?
Then there's her legacy as Secretary of State. Part of this was damage control - she visited 112 nations - rolling out US soft power to repair the harm done to America's image by the George W. Bush neo-conservatives.
But there's always been a clenched fist inside the velvet glove. She backed sanctions against Iran - that arguably helped broker what may be a rapprochement with the US - and, last month, air strikes against Syria.
She also faced down Republican efforts to cripple her prospects, after US security flaws were exposed when four Americans, including the US ambassador, were killed by armed men in a 2012 raid in Benghazi, Libya. Besides meeting politicians and diplomats, Clinton touted a transformative "21st century diplomacy" that focused on using "smart power" to tackle grassroots issues.
In 1995, as First Lady, she led the US delegation to a United Nations conference in Beijing and stressed that "women's rights are human rights". This remains a core belief, linked to sustainable development and political stability.
"It's time for a full and clear-eyed look at how far we have come, how far we still have to go and what we plan to do together about the unfinished business of the 21st century - the full and equal participation of women," she told the Clinton Global Initiative last week in New York. It sounds like unfinished business and a potential 2016 presidential election plank.
