Photo

In the third sit-down national TV interview of her presidential campaign, Hillary Rodham Clinton said the candidacy of Donald J. Trump was a “bad development for our American political system,” rejected the implication that her campaign was irrevocably damaged by the email controversy and took a veiled jab at Senator Bernie Sanders, whose populist message has drawn big crowds and given him a lift in recent polls in Iowa and New Hampshire.

“You can wave your arms and give a speech but at the end of the day are you connecting with and really hearing what people are either saying to you or wishing that you would say to them?” Mrs. Clinton told MSNBC’s Andrea Mitchell on Friday, without directly naming Mr. Sanders.

When asked by Ms. Mitchell about new polls that show a growing number of Americans do not trust her amid ongoing questions over her use of a private email, Mrs. Clinton said she was “confident” voters would trust that she was best positioned to help them improve their economic situation.

“The American people will know they can trust me when it comes to standing up to them and advocating for them and being their champion,” Mrs. Clinton said.

Asked why she deleted thousands of personal emails from her private server, Mrs. Clinton said her lawyers had meticulously examined the emails, determining which were work-related and which were personal, before handing over some 55,000 pages to the State Department. “I was asked ‘Do you need to keep your personal emails?’ and I said, ‘No, we don’t. You can delete those,’ ” she told a persistent Ms. Mitchell.

The State Department, she said, recently informed her lawyers it would be returning 1,200 additional emails because they were deemed strictly personal and not work-related.

Mrs. Clinton defended her close aide, Huma Abedin, whose special arrangement to take on outside consulting work while serving at the State Department was viciously criticized last week by Mr. Trump. “He has attacked so many people including my close aide and myself and many other people,” she said. “I think it’s an unfortunate development in American politics that his campaign is all about who he’s against.”

She said she was not involved in Ms. Abedin’s arrangement, but that “everything she did was approved under the rules as they existed in the State Department.” Concerning Mr. Trump. she said, “He’s great at innuendo and conspiracy theories and defaming people.”

Mrs. Clinton declined to comment on any policy differences she had with Vice President Joseph R. Biden Jr., who is contemplating whether to seek the Democratic nomination. “I’m not going to address any of the political questions around my friend Joe Biden,” she said.

She said she felt confident about her own candidacy, but could understand why Americans were frustrated with their economic circumstances and looking for answers from a range of candidates. “Sometimes those answers are bombastic and very ideological,” Mrs. Clinton said. “But I can understand why people are looking for some way out of their own problems, particularly their economic problems.”