Facing persistent -- and growing -- criticism of her use of a private email server when she was secretary of state, Clinton's team shifted gears on Wednesday to mount a more muscular defense of the Democratic presidential front-runner.

The Clinton camp dispatched a host of top aides and surrogates -- even pulling some from vacation -- to try to dismiss the drama as the product of a hyper-partisan political environment and an overwrought media. And it took the unusual step of convening a conference call with reporters so aides could try to gain more control over the story.

"We do think people have concerns and questions," Clinton communications director director Jen Palmieri told reporters. "We think it's really confusing, and want to try to answer them."

That's a vastly different approach to the one Clinton took on the campaign trail over the past week. She tried joking about it, downplaying it and chalking it up to "partisanization." But nothing quelled the controversy and, in some cases, Clinton's comments only intensified the criticism.

Challenges on multiple fronts

The new strategy comes as Clinton is facing challenges on multiple fronts.

A CNN/ORC poll released Wednesday found that Bernie Sanders is gaining strength in the Democratic primary while Donald Trump could be a competitive rival for Clinton in the general election. Meanwhile, there's persistent speculation that Vice President Joe Biden might enter the race. And focus on her emails has grown since she turned over her server to the Justice Department last week.

Trump slammed Clinton for her handling of the emails in a Wednesday interview with CNN's Chris Cuomo.

"What's the purpose of it?" Trump said. "You know, it's always skirting the edge. What's the purpose of it? In the end, she had something in mind. She didn't want people to know or something. But what is she doing? Why is she doing it?"

The Clinton campaign on Wednesday sent aides and allies such as Palmieri, Brian Fallon and James Carville -- who said he'd cut off his vacation early -- onto television in an attempt to contain the story.

Their argument: Clinton did nothing wrong; the emails contained no information that put U.S. interests at risk and she's done everything she can do.

Also: Ultimately, none of it matters.

"It's just mostly stupid media people talking to other stupid media people, making stuff up and spinning themselves up on something that's not gonna amount to a hill of beans," Carville, a long-time political adviser to Bill and Hillary Clinton, told MSNBC

On Bloomberg, Palmieri said the former secretary of state hadn't meant to hide anything by using a private server -- she just "really didn't think it through."

And on MSNBC, Palmieri said: "I think when you get to the point that you're answering questions about wiping servers that you're nearing the end of legitimate questions for her to answer."

Legitimate or not, Palmieri acknowledged on the conference call with reporters that the Clinton campaign has changed its strategy for handling the emails. She admitted that, while the issue hasn't been raised with Clinton in her town hall meetings, it is on voters' minds.

Not a laughing matter for some

In front of a friendly audience at the Iowa Democratic Wing Ding dinner on Friday night, Clinton tried to defuse the issue with a joke. She brought up her newly-launched account on Snapchat -- the social messaging app where users' messages and photos disappear shortly after the recipient sees them.

"I love it," Clinton said. "Those messages disappear all by themselves."

That joke, though, led to criticism that Clinton is tone-deaf -- and opened her up to responses like that of Republican Wisconsin Gov. Scott Walker, tweeting photos of blacked-out emails and saying he'd caught them on Snapchat.

On Saturday, at the Iowa State Fair, Clinton chalked the criticism up to partisan politics, saying the reason the issue remains alive is that Republicans are trying to score political points -- and the political press is allowing it.

"This is the usual partisanization -- I may have just made up a word -- of anything that goes on," she said with a chuckle.

The humor was totally gone on Tuesday, when Clinton addressed reporters in Las Vegas. Pressed by Fox News' Ed Henry about reports that the Justice Department found an attempt to wipe Clinton's server clean of data, the former secretary of state played dumb, saying: "What, like with a cloth or something?"

She insisted she'd done nothing wrong, saying it is her right to keep personal emails private.

"They can do whatever they want to with the server to figure out what is there and what is not there," Clinton said of Justice Department investigators and intelligence analysts combing through her emails. "That is for the people investigating it to try to figure out. But we turned over everything that was work related -- every single thing. Personal stuff, we did not, I had no obligation to do so. And didn't."

She also slipped into a legalistic defense, insisting that her use of a private server was only out of convenience and wasn't impermissible.

"In retrospect, this didn't turn out to be convenient at all and I regret that this has become such a cause celebre. But that does not change the facts," she said. "The facts are stubborn -- what I did was legally permitted."

The exchange had clearly struck a nerve. As Clinton finished taking questions and walked away from reporters, one shouted to ask whether the email controversy will continue dogging her campaign.

Exasperated, Clinton turned and threw her arms up in the air.

"Nobody talks to me about it, other than you guys," she said, and turned and walked out.

Controversy not going away, at least for now

If voters aren't asking Clinton about the emails, their views of her candidacy are still being shaped by the controversy. The CNN/ORC poll shows that 56% of Americans say she did something wrong by using a personal email account on a private server during her tenure as America's top diplomat.

Of course, she remains the Democratic front-runner, with 49% support -- a mark any of the Republican candidates would love to hit. And the email controversy hasn't hurt Clinton as much among her own party's voters.

Still, the intelligence community's review of Clinton's emails has provided a string of reports about items in her inbox being subsequently classified.

On Wednesday's conference call, Fallon, a Clinton spokesman, attempted to take the air out of any future reports that additional emails have been flagged by intelligence officials as classified or otherwise problematic.

He pointed to Henry Kissinger documents that remain classified even though they are more than 40 years old. And he chalked Clinton's emails' subsequent classification up to a "culture of classification that exists in certain corners of the government, especially the intelligence community," saying that the campaign doesn't want "bureaucratic squabbling" to delay the release of more of Clinton's emails.

"As the number of intelligence community lawyers multiply here," Fallon said, "it really shouldn't come as any surprise that they're going to start flagging a higher number of emails for further review."