By Niall Stanage - 10-19-16 06:00 AM EDT
Donald Trump and Hillary Clinton are set to face a huge national audience together for the last time before Election Day.
The stakes could hardly be higher Wednesday in Las Vegas, where the two major-party presidential nominees will meet for their third and final debate.
For Trump, the encounter could be his last opportunity to make a campaign-changing case against his Democratic opponent. The Republican trails by significant margins in both national and battleground state polls, and he desperately needs to change the trajectory of the race.
For Clinton, the challenge is simply to avoid damaging mistakes, a task that could be made harder by the embarrassing emails from her campaign released by WikiLeaks. Many observers also expect the moderator, Chris Wallace of Fox News, to be more inclined to question Clinton with rigor than the moderators of the fall's previous two debates.
Both candidates also have the sheer size of the debate audience to consider.
The first Trump-Clinton clash, held just outside New York City, was the most-watched presidential debate in history, with a TV viewership of around 84 million people. The audience fell off significantly for the second debate, in St. Louis, to 66.5 million. But even if the audience size erodes still further for the Vegas encounter, there are likely to be more than 50 million viewers.
Nothing else in the remaining three weeks of the presidential campaign offers the chance to communicate directly with so many voters at one time.
While some Republicans are increasingly gloomy about Trump's chances, others evince optimism about the opportunity the debate presents.
"I think it is extremely important for the Trump campaign," said J. Hogan Gidley, a GOP strategist who worked for former Arkansas Gov. Mike Huckabee's presidential campaign earlier in this cycle and for former Sen. Rick Santorum (Pa.) during his 2012 bid. "You can help yourself immensely. And I think this is an amazing opportunity in light of so many issues that have come up."
Gidley highlighted various details that have emerged from the apparent hack of an email account belonging to Clinton's campaign chairman, John Podesta, and from the continuing controversy over her use of a private email server while she was secretary of State.
On Tuesday, President Obama pushed back on the idea that recently revealed FBI notes show the State Department had pressured the FBI to declassify one of Clinton's emails.
"The notion or the accounts that have been put out there are just not true," Obama said in a news conference in the White House Rose Garden.
Critics say they see official wrongdoing in the suggestion of a deal in which the FBI would receive State Department approval to station more agents in Iraq in exchange for declassifying the email. Officials from both agencies say that characterization is wrong.
The separate matter of the Podesta hack has also exposed details that are politically awkward - though hardly campaign-altering - for Clinton, including her efforts to thwart the presidential primary challenge from Sen. Bernie Sanders (I-Vt.) and her campaign's fears that she could be seen as too close to Wall Street.
All of those subjects could make for promising lines of attack for Trump against Clinton. But some outside experts caution that he has to be careful.
The GOP nominee is stuck at around 40 percent support in most national polls. That is not enough to win, even if Libertarian Party nominee Gary Johnson and Green Party nominee Jill Stein pull a share of the vote.
Consequently, Trump needs to find a way to expand his support, and many observers are skeptical that an attack on Clinton is the way to achieve that. They also say that, while attacks on the email issue or the activities of the Clinton Foundation could be seen as fair game, a reprise of the second debate, when Trump raised former President Bill Clinton's history with women, could be counterproductive.
"I hesitate to think what those 90 minutes are going to be like," said Mitchell McKinney, a professor of political communication at the University of Missouri. "If [Trump] triples down and decides he has to get even more angry and attack-oriented, I don't understand that logic. He tried it twice."
McKinney, like many others, argues that Hillary Clinton has a much simpler task as she takes the stage as the University of Nevada in Las Vegas.
"I think her goal is just to maintain the same level of performance as she has in these past two debates," he said. "And she hopes things will continue in her favor until Election Day."
The first debate, in particular, seemed to prompt a shift in the polls toward Clinton - proof in itself that debates still matter, even in a campaign as unusual as this one.
Now the question for Trump is whether he can reverse that trend in 90 minutes in Las Vegas.