WASHINGTON — Challenged anew by Bernie Sanders, Democratic front-runner Hillary Clinton is reverting to some of the same themes — even strikingly similar attack lines — from her 2008 primary loss to Barack Obama.

Clinton is leaning hard on an experience-above-all-else argument, sarcastically reminding people that as a former first lady and secretary of state, she wouldn’t need a tour of the White House if elected president. She made a similar pitch eight years ago, only to find an electorate in search of change, not a seasoned Washington hand.

Clinton is also suggesting that Sanders, who backs a single-payer health care system and free tuition at public colleges and universities, is pitching policies that are unachievable in a divided government.

“I wish that we could elect a Democratic president who could wave a magic wand and say, ‘We shall do this, and we shall do that,’ “ Clinton said this week in Iowa. “That ain’t the real world we’re living in!”

Her comments mirrored one of her most searing criticisms of Obama from eight years ago, when she suggested his plan for fulfilling lofty campaign promises amounted to hoping “the skies will open, the light will come down, celestial choirs will be singing and everyone will know we should do the right thing and the world will be perfect.”

“Maybe I’ve just lived a little long, but I have no illusions about how hard this is going to be,” Clinton said at the time. “You are not going to wave a magic wand and have the special interests disappear.”

Clinton’s recent comments startled some supporters. They privately fear she risks falling into the same traps that contributed to her downfall in 2008: underestimating a rival and misreading voters eager for outsider candidates in both parties.

“Working in Washington itself isn’t winning anybody friends this election cycle,” said Ben LaBolt, who worked on Obama’s two presidential campaigns.

“So it has to be more about the ability to tackle significant challenges and how experience has demonstrated that she’s capable of doing that.”

With less than three weeks until voting begins, much of the enthusiasm in the Democratic race appears to reside with Sanders. The Vermont senator has consistently led preference polls in neighboring New Hampshire, and now appears to be gaining momentum in Iowa as well, buoyed by support from many of the young, progressive voters who backed Obama eight years ago.

It’s unclear, however, whether Sanders can broaden his appeal and win the support of other Democratic constituencies that helped Obama defeat Clinton, including black and Hispanic voters. And despite the echoes of 2008 now permeating Clinton’s remarks, her campaign has worked aggressively to avoid some of the operational missteps that also marred her first White House bid.

Still, there’s no doubt Sanders’ unexpected strength has the Clinton campaign on edge. After spending much of last year engaged in polite policy disagreements, even going long stretches without mentioning Sanders by name, Clinton’s team has unleashed a torrent of attacks on Sanders, focusing in particular on his record on gun control and his refusal to detail the cost to taxpayers of his health care plan.

“One can only draw the conclusion that the Sanders campaign does not want to outline what would amount to a massive tax hike on working families,” said Jake Sullivan, Clinton’s senior policy adviser.

David Axelrod, another veteran of Obama’s political team, said that while Clinton may have valid points about the feasibility of Sanders’ policy proposals, she risks once again being seen as someone who will work within the system, not someone who will remake it.

“People in Iowa, they want to aspire,” Axelrod said. “They want to feel that their vote matters and you can actually change things.”

A loss in the first two states wouldn’t be a death-knell for Clinton’s White House hopes. She has a broad political organization across the country and is expected to perform better in the more racially diverse states that vote after Iowa and New Hampshire.

Still, back-to-back losses would unleash a flurry of questions about Clinton’s ability to close the deal with Democrats in a race where the field was essentially cleared for her benefit.

Some Clinton supporters say a tough challenge from Sanders and a longer primary than initially expected could ultimately work to her advantage. Clinton often appears more comfortable as an underdog than as a front-runner, and was most effective in the 2008 race after suffering several losses, though her resurgence came too late to overtake Obama.

“She’s at her best when she’s fighting for it,” said Maria Cardona, a Clinton supporter who worked for the 2008 campaign.