Heading into the first Democratic presidential debate, Hillary Clinton may be the closest she has ever been to the White House in her political career. Her campaign can tick off significant backing from the party's elite, top fundraising dollars and the commanding lead in Democratic support -- yet undercutting her viability, she earned her poorest favorability ratings this week in more than two decades.

Ahead of Tuesday night's debate in Las Vegas, the latest CBS poll shows Clinton's favorability numbers have plummeted to the lowest since 1992. More than half of voters nationwide -- 53 percent -- saw her unfavorably rather than favorably in the survey conducted by phone Oct. 4-8. 

Elections divide the electorate by nature, and candidates are expected to see higher unfavorability ratings as the race marches on. But Clinton entered the 2016 race with more support than in the 2008 election season, making her recent fall all the more noteworthy, the New York Times reported. 

The drop in positive perception is a testament to the unusual factors at play for the former U.S. secretary of state, U.S. senator and first lady this election season, pundits say. Beyond the standard opposition forces -- both Democratic challengers and Republicans -- Clinton weathers heat from an FBI investigation and congressional hearings on actions related to the Sept. 11, 2012 terror attacks in Benghazi, Libya. 

To put it succinctly: "When you get focused attention on bad news, that's going to have an effect on the public," said Blaine Garvin, a professor of politics at Gonzaga University in Spokane, Washington.

Republican politicians have taken some responsibility for her poll numbers. "Everybody thought Hillary Clinton was unbeatable, right? But we put together a Benghazi special committee. A select committee. ... What are her numbers today?" U.S. Rep. Kevin McCarthy told Fox News earlier this month.

But pundits argue that Clinton's favorability hemorrhaged with her reaction to the controversies surrounding her use of a private email server during her tenure as secretary of state and the congressional investigation into the Benghazi attacks, which resulted in the deaths of U.S. Ambassador J. Christopher Stevens and three other Americans.  

"She needs to step forward and take more responsibility for issues like the email server and Benghazi," said Michael Shires, an associate professor of politics at Pepperdine University in Malibu, California. "Voters want someone to take more definitive responsibility and someone they trust as a leader. She needs to make some disclosures and create extra access to make herself seem more transparent."

Democratic voters have said as much in the polls. Along with whether the candidate cares about people like them, voters chose honesty and trustworthiness as the top qualities in deciding their vote for the party's nominee, according to the latest CBS poll. Vice President Joe Biden outscored Clinton in this measure: While 68 percent see Clinton as honest and trustworthy, Biden was viewed by 85 percent as possessing these traits, while U.S. Sen. Bernie Sanders of Vermont was viewed positively by 50 percent. Biden is not a declared candidate for president, while Sanders is. Other Democrats seeking the presidency are former Rhode Island Gov. Lincoln Chafee, Harvard professor Lawrence Lessig, former Maryland Gov. Martin O'Malley and former U.S. Sen. Jim Webb of Virginia.

In terms of favorability among Democratic voters, Clinton trails Biden, and many view her drop in the polls as his invitation to enter the race. Biden maintains a marginal lead over Clinton with 71 percent favorability to her 69 percent.

"Vice President Biden would be one of those threats that would change the map," Shires said.

But onstage at the Democratic presidential debate Tuesday, Sanders is considered to be Clinton's biggest threat. The Vermont senator, who almost closed in on Clinton's third-quarter fundraising total, polls 19 points behind her for the Democratic nomination, according to CBS. 

"She needs to deliver to those who already support her and she needs to convince [those] she lost to Sanders that she's a personable candidate," said Caroline Heldman, a professor of politics at Occidental College in Los Angeles. 

The numbers are unlikely to affect Clinton's fundraising efforts, according to pundits. In spite of declining popularity, Clinton has already raised nearly twice as much as Sanders, and reportedly far exceeds anyone else on the campaign trail. Her team reported she secured most of her $100 million goal for the primary race early in the season. By the end of the third quarter, she reported $75.6 million from donors. Retired neurosurgeon Ben Carson, the second-place GOP candidate, behind Donald Trump, raised about $30.7 million in total by comparison.

Beyond Tuesday's debate and the Democratic nomination, the general election could still present a difficult challenge for Clinton. To boost her ratings, Clinton will have to make more explicit appeals to the Black Lives Matter social justice movement and opponents of the Keystone XL pipeline proposal, Heldman said. She said strong positions on these issues at the Las Vegas debate could help reframe Clinton as a less-traditional candidate. 

"I think we are going to see the ugliest race we've ever seen," Heldman said. "For some voters, it's a very threatening to think about a woman holding this position. On the Republican side, there is very well-organized opposition and one that is more extreme than we have seen in the past. I think the Benghazi committee is a perfect example of using government resources to take down the opposing candidate."

Heldman warned that more damage may further hurt Clinton's favorability numbers. "I don't think we have seen the bottom of it," she said.