AMES, Iowa — With her lead in the Democratic presidential race in Iowa effectively vanished, Hillary Clinton tore into insurgent rival Bernie Sanders on Tuesday over a litany of issues from health care to gun control.

Clinton charged that Sanders’ policy proposals were unrealistic, that the Vermont ­senator would raise taxes on middle-class families, and that he could not be trusted to fight special interests and protect President Obama’s achievements, including his signature health care law.

On health care, she argued that Sanders’ ‘‘Medicare-for-all’’ plan would jeopardize the Affordable Care Act and effectively turn over health coverage programs to the states, many of them led by Republican governors.

‘‘If that’s the kind of ‘revolution’ he’s talking about, I’m worried, folks,’’ Clinton said, a reference to Sanders’ call for ‘‘a political revolution.’’

Clinton’s speech to a few hundred supporters on the campus of Iowa State University was striking in its sharp tone and the breadth of her attacks against Sanders. Her intensified assault came as a new Quinnipiac poll Tuesday showed Sanders overtaking her in Iowa, 49 percent to 44 percent.

Clinton accepted the endorsement of the Brady Campaign to Prevent Gun Violence and used the occasion to tear into Sanders for his 2005 Senate vote that gave immunity to gun manufacturers. That bill was a major priority for the National Rifle Association.

Clinton mocked Sanders for claiming that he was voting in line with the interests of his rural state with a deep hunting tradition.

‘‘He says, ‘Well, I’m from Vermont,’?’’ Clinton said. ‘‘Pat Leahy, the other senator from Vermont, voted against immunity for the gun lobby. So, no, that’s not an explanation.’’

Sanders has vowed to break up the big banks, but Clinton asserted Tuesday that she has stood up to special interests throughout her career, including on Wall Street. She said she went after derivatives and corporate executive compensation, and that she helped influence the Dodd-Frank financial regulation bill, which passed after she left the Senate to become secretary of state.

‘‘Don’t talk to me about standing up to corporate interests and big powers,’’ Clinton said. ‘‘I’ve got the scars to show for it, and I’m proud of every single one of them.’’

Speaking more broadly about the challenges of the presidency, Clinton said she was the only candidate prepared to do all the duties of the office.

She spoke movingly about her role in the White House Situation Room during the Osama bin Laden raid, calling it ‘‘one of the most tense days of my life.’’

Without mentioning Sanders by name, Clinton implicitly suggested he was naïve to think he would be able to implement his ideas, especially with a Republican-controlled Congress.

‘‘This is hard work,’’ she said. ‘‘I wish we could have a Democratic president who could wave a magic wand and say, ‘We shall do this, and we shall do that.’ That ain’t the real world we’re living in!’’

Clinton appeared to relish laying into Sanders. ‘‘We’re getting into that period before the caucus that I kind of call the ‘Let’s get real period,’?’’ she said. ‘‘Everybody’s been out there, lots of good energy, I love it. I love the spirited debate on our side.’’

In recent days, Clinton has been highlighting her perceived electability, something her campaign is trumpeting in a television advertisement airing in ­Iowa.

Pointing to her longevity in the public eye, she suggested that she was the only Democratic candidate who could withstand the Republican attacks in a general election.

‘‘You’ve got to know what you stand for, you’ve got to be able to defend it, and you have to withstand the barrage of attacks that will come against our Democratic nominee,’’ she said. ‘‘I am still standing.’’