Are Hillary Clinton’s e-mails scandal or mere controversy? New evidence.

Hillary Clinton isn’t the only politician to have used a private e-mail account to conduct government business. But as the front-runner for the White House, she’s getting the most scrutiny as troubling evidence keeps mounting.

It’ll be up to Democrats to decide whether mounting questions about Hillary Rodham Clinton’s e-mail account – or accounts – ends the romance with the current 2016 presidential front-runner.

But as the controversy unfolded this week, Democrats were reported to be “showing signs of stress.”

“In interviews with more than three dozen Democratic activists, donors, and officials from across the country – including many in the influential presidential nominating states of Iowa, New Hampshire, and South Carolina – some were scathing in their criticism over the revelations, while others admitted to being unnerved,” Politico.com’s Gabriel Debenedetti wrote.

In any case, it increases party nervousness about lack of depth in the presidential field.

“It adds more reason to get other people involved in this process, to make sure we have other strong, good candidates running,” Larry Hogden, chairman of Iowa’s Cedar County Democrats, told the website. “Because, who knows? She could implode totally.”

Predicting a Clinton implosion may be premature. But the bad news for her in fact keeps coming, even if it just prolongs the distraction and never adds up to much. (The story began with a New York Times report that as secretary of state she had used only a private e-mail address, and then continued when the Associated Press revealed that Mrs. Clinton was operating her own e-mail server, giving her a greater level of control over her communications.)

By Friday, Politico was reporting that “the State Department has had a policy in place since 2005 to warn officials against routine use of personal e-mail accounts for government work, a regulation in force during Hillary Clinton’s tenure as secretary of state that appears to be at odds with her reliance on a private e-mail for agency business.”

Perhaps more damaging (at least more suspicious-sounding), Fox News reported Friday that “Clinton appears to have established multiple e-mail addresses for her private use, and possibly the use of her aides, under the domain of ‘clintonemail.com,’ according to a prominent member of the hacking community who supplied independent research data, conducted with high-tech tools.”

The hacker used an open-source tool called “The Harvester” to search well-known platforms such as Google, Bing, LinkedIn, Twitter and others for stored references to e-mail addresses seen using a particular domain, in this case clintonemail.com, according to Fox.

As secretary of state, Clinton is said to have used a single e-mail address: hdr22@clintonemail.com. But there may have been others.

“Given the sequential similarities to hdr22@ I suspect some others found by my search may also have been used by HRC,” the hacker said. “I suspect hdr18 – hdr21 may have been used by HRC as well as h@clintonemail.com and hillary@clintonemail.com. I’d also be interested to learn if there were ever hdr1@ thru hdr17@.”

The State Department is now wading through thousands and thousands of Clinton e-mails.

An official at State tells the Washington Post that Clinton’s use of personal e-mail did not automatically break the rules, but the analysis could show whether work e-mails sent from her personal account included sensitive information that is typically required to be handled on a system that meets security protocols.

What does all of this portend for Clinton in 2016?

“There is a widespread feeling, among political professionals and the commentariat, that Clinton, having chosen to delay the launch of her campaign, might be on the point of losing control of its narrative,” John Cassidy writes in The New Yorker. “But it can also be argued that, by publishing these stories now, the media might end up doing Clinton a favor. In the public-relations industry, the standard method of managing potential crises is to get the worst news out early, seek to weather it, and then argue that subsequent revelations are mere wrinkles on a story that has already been told.”

Delaying the release of his tax returns for 2011 and 2012 hurt Mitt Romney in the last presidential election, Cassidy points out.

Clinton isn’t the only presidential hopeful who’s had e-mail problems.

“In the spirit of transparency,” Jeb Bush released eight year’s worth of e-mails from his time as governor of Florida. But as the Monitor’s Peter Grier reported last month, “In their rush to get the e-mails published, Bush’s staff apparently did not notice that some of the thousands and thousands of e-mails contained names, addresses, e-mail addresses, and even Social Security numbers for average Floridians.”

Writing in the Daily Beast, Lloyd Green reports that before Scott Walker was elected governor of Wisconsin, when he was Milwaukee County executive, “Walker’s staff kept a secret e-mail system and set up a secret wireless router in Walker’s government office that commingled government and campaign business on private Gmail and Yahoo e-mail accounts.”

The investigative website ProPublica reported last year that aides to New York Gov. Andrew Cuomo have used private e-mail accounts, which can help hide communications on public business, despite state rules barring the practice.

But for now, the focus is on Clinton, whose friends are hoping for the best.

"I can assure you, come November 2016, if she becomes a candidate, there will be no one going to the polls thinking about these e-mails," former Pennsylvania Gov. Ed Rendell, a Clinton ally, told the AP.

Perhaps.