The senator from Vermont is Hillary Clinton’s rival in the contest for the Democratic presidential nomination.

The senator from Vermont has become Hillary Clinton’s chief rival in the contest for the Democratic nomination.

The senator from Vermont has become Hillary Clinton’s chief rival in the contest for the Democratic nomination.

Hillary Clinton’s new barrage against Bernie Sanders, the Democratic presidential primary opponent she has all but ignored through most of her campaign, is having an effect — though probably not the one she intended.

Sanders’s underdog campaign said it is seeing a surge of contributions as a direct result of the new attention it is getting from the Democratic front-runner, with money coming in at a clip nearly four times the average daily rate reported in the last quarter of 2015.

In its email appeals for money, the campaign accused the Clinton campaign of making “vicious and coordinated attacks” on Sanders’s health-care plan, which calls for a government-run system. Sanders’s strategists are also considering rolling out advertising beyond the early-contest states where it is airing spots now.

The former secretary of state and her team have stepped up their criticism of Sanders on a variety of fronts in recent days as polls have begun to show him edging even with her in Iowa — and, for the first time, looking competitive in a national poll. But the Clinton strategy may be backfiring in some ways.

“Thanks, Team Clinton,” Sanders spokesman Michael Briggs said Wednesday afternoon.

Hillary Clinton challenged Bernie Sanders's stance on gun control during a campaign event in Ames, Iowa, on Jan. 12. (Reuters)

“As of now, we are at about $1.4 million raised since yesterday when the panic attacks by the Clinton campaign began,” Briggs said. “We’ve gotten 47,000 contributions. We’re projecting 60,000 donations. Even for our people-powered campaign, this is pretty darn impressive.”

Sanders strategist Tad Devine said the campaign may go on the air with TV ads outside the three early-contest states of Iowa, New Hampshire and Nevada. Sanders’s team now feels pressure to put out its own message across the map before Clinton has a chance to define it on her terms. “That is something we are considering as we speak,” Devine said.

[With the first two states in danger, Clinton goes on the attack against Sanders]

A New York Times-CBS News survey released Tuesday showed Clinton leading Sanders by just seven percentage points, 48 percent to 41 percent, among Democratic primary voters. A month ago, that same poll showed her with a 20-point lead nationally.

Early Thursday, a new Des Moines Register/Bloomberg Politics poll showed the race in Iowa as statistically tied. Clinton had slipped nine percentage points from a month ago, and now led Sanders by 42 percent to 40 percent, with a 4.4 percent margin of error.

“I am not nervous at all,” Clinton said in an interview Wednesday on NBC’s “Today” show. “I’m excited about where we are.”

Her actions and those of her surrogates speak otherwise.

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At the last Democratic debate in December, Clinton barely acknowledged that Sanders was on the stage with her, except when responding to his criticisms. Already sounding like a general-election candidate, Clinton trained nearly all her fire on GOP front-runner Donald Trump.

In more recent interviews, speeches and advertising, Clinton has become more vocal and blunt in her denunciations of her Democratic opponent, accusing him of buckling to the gun lobby and of putting forward naive and unrealistic proposals.

Clinton has also suggested that Sanders, a democratic socialist, is unelectable against whoever the Republicans end up nominating.

[Clinton and Sanders try to erode each other’s strengths in tightening race]

Even her daughter, Chelsea Clinton, got into the act, bashing Sanders during her first campaign appearance on behalf of her mother this election season.

“Senator Sanders wants to dismantle Obamacare, dismantle the [Children’s Health Insurance Program], dismantle Medicare and dismantle private insurance,” Chelsea Clinton said at a stop in New Hampshire. “I worry if we give Republicans Democratic permission to do that, we’ll go back to an era — before we had the Affordable Care Act — that would strip millions and millions and millions of people off their health insurance.”

Her argument echoed what her mother has been saying. What neither mentions is that Sanders is proposing a single-payer system in which all health care would be financed through the government, as Medicare is now. Single-payer health care has long been a cherished hope of liberals, who see it as the only way to assure that all Americans receive medical coverage.

On Tuesday afternoon, Sanders’s campaign blasted out an email funding appeal: “We have made tremendous gains in Iowa, but if we lost because Hillary Clinton’s campaign scared voters into thinking Bernie’s plan would cost them their coverage, it could set our vision for universal health care back at least a generation. We simply cannot let that happen.”

Since he announced his candidacy last April, Sanders has been drawing huge crowds, sometimes on the scale of Trump’s. Over the course of the campaign, his fundraising has steadily grown, bringing him almost on par with Clinton in the final quarter of last year, when he reported average daily takes of $362,637.36 to her $406,593.41. Those numbers, by comparison, also show how significant the $1.4 million haul was this week.

The latest polling suggests that liberal support is not the only area where Clinton is struggling to beat back Sanders.

A new Quinnipiac University poll out of Iowa shows Sanders now holding a narrow, five-point edge, upending Clinton’s 11-point lead in the same survey last month. The biggest shifts were among moderates and conservative Democrats, voters with whom Clinton had run most strongly in December. Her 22-point lead with them last month shrank to two percentage points in the latest survey.

Among voters who said they are most concerned with the economy, Sanders held a 29-point lead, up from only three points last month.

For all of her formidable political assets — and the name recognition that comes with having been a first lady, a senator and the nation’s chief diplomat — Clinton is running in an environment when voters of both parties appear thirsty for change.

Sanders’s signature issues, reducing income inequality and reining in Wall Street, are in tune with the Democratic base.

“I think that Bernie is speaking to a yearning that is deep and real. And he has credibility on it. And that is the absolute, enormous concentration of wealth in a small group of people, with the middle class now being able to be shown being left out,” Vice President Biden said in an interview Tuesday on CNN. Biden added that “it’s relatively new for Hillary to talk about that. Hillary’s focus has been other things up to now. No one questions Bernie’s authenticity on those issues.”

Scott Clement and Matea Gold contributed to this report.