Heidi M. Przybyla

USA TODAY

Hillary Clinton and Donald Trump square off in the first presidential debate on Monday night at Hofstra University.

The forum in Hempstead, N.Y., could prove pivotal, with polls showing many voters unsatisfied with their options in November. “The debates could completely change the calculus,” said David Cohen, a professor who teaches a course on the American presidency at the University of Akron.

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Here are five things Clinton needs to do:

1. Play offense

With polls showing a tightening race, the Democratic nominee has little choice but to go on the offensive. “There’s a whole basket of issues she can really use in this debate,” said Maria Cardona, a former senior adviser to Clinton’s 2008 campaign. She cited Trump’s proposed temporary ban on Muslims entering the United States, his call for deporting undocumented immigrants who aren’t criminals and the fact that he has drawn support from white supremacists like David Duke. Clinton also needs to excite base voters by showing she can land some punches.

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2. Be more likable

With unfavorable ratings similar to Trump's, It may be Clinton’s final chance to change voters' perceptions of her.

Debates can be defined by single moments, meaning she must be mindful of her mannerisms, as Gore learned in 2000 when he sighed and rolled his eyes as then-Texas governor George W. Bush spoke. “Trump has an uncanny ability to read the person on the other side of the table,” said New York City real estate developer Peter Kalikow, who's worked alongside Trump in Manhattan. “If she arrogantly dismisses him as bluster she is making a strategic mistake.”

The same goes for when it’s her turn on the hot seat. For instance, the former secretary of State thinks she’s been asked and answered every possible question about her private email server. She’ll get more — and she must gamely answer them while showing a sense of humor that’s not snarky.

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3. Outline a positive vision

Clinton’s campaign is struggling to reassemble President Obama’s successful coalition that relied on strong turnout from young voters and African Americans. While Clinton holds a huge advantage over Trump among blacks (83 points, according to a recent New York Times survey), that doesn’t predict turnout, which could be lower than it was in 2008 and 2012.

To that end, the campaign has been trying to emphasize her biography, in particular her work on behalf of children and families since her first job out of law school working for the Children’s Defense Fund. She needs to take opportunities at the debate to highlight this experience, as well as policy proposals on student debt relief and criminal justice reform — and contrast them with Trump’s.

2016 Poll Tracker - USA TODAY

4. Go off script

One of the most-oft repeated criticisms of Hillary Clinton is that she’s too scripted. Going against an unpredictable figure like Trump increases the potential she’ll be forced to go off script. That may not be a bad thing. In fact, her campaign has a video crew following her to capture such moments, which they believe are the most effective ways to humanize her.

It was in a 2008 debate when the moderator asked her about her likability problem that she replied: “Well, that hurts my feelings.” Her competitor, then-senator Barack Obama, replied: “You’re likable enough, Hillary.” It was one of her best moments and one of his worst.

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5. Have a compelling answer about Iraq and Syria

Voters’ top concerns about Clinton are her judgment over U.S. policy in Iraq, Syria and Libya followed by her use of a private email server while secretary of State, according to the latest Wall Street Journal/NBC News poll.

It’s also the focal point of Trump’s chief critique of her, that she has "bad judgment." Clinton needs to give American voters a straightforward explanation of what she learned from her vote authorizing the use of force in Iraq and how this experience will inform her policy approach to the Middle East going forward.

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