The Bloomberg poll, released Tuesday, found that just 39% of Americans view Clinton favorably, while 41% view Trump favorably. That two-point difference falls within the survey's margin of error, which was plus or minus 3.1 percentage points.
Former President Obama, by comparison, was viewed favorably by 61% of respondents, according to the poll.
"There’s growing discontent with Hillary Clinton even as she has largely stayed out of the spotlight," pollster J. Ann Selzer, who oversaw the survey, told Bloomberg. "It’s not a pox on the Democratic house because numbers for other Democrats are good."
The poll found that Clinton's current favorability rating is the second-lowest it has been since 2009, when Bloomberg began tracking her. In September 2015, her favorability hit a low of 38%.
Trump's approval ratings have continued to reach record lows, compared to other U.S. presidents at this point in their tenures. Even as he faces a variety of challenges in his presidency—including the failure of the Republican health care bill and investigations into Russian meddling in the election—Trump has continued to criticize Clinton and her campaign, rehashing old debates and raising questions about Clinton's primary victory over Vermont Sen. Bernie Sanders.
Clinton, who is working on a new book that will address her presidential campaign, has spoken out in several interviews and speeches since losing the election. She also launched a Political Action Committee dedicated to promoting liberal causes and candidates.
The poll of 1,001 adults by phone was conducted between July 8 and 12.