Here’s One Expert’s Advice for the Candidates at the Democratic Debate

Unlike their Republican counterparts, the Democratic presidential candidates debating Tuesday come from very different places.

Former Secretary of State Hillary Clinton is the one-time frontrunner, now seeking to regain her hold on the field. Vermont Sen. Bernie Sanders is the challenger, seeking to continue his momentum. Former Maryland Gov. Martin O’Malley is the underdog, hoping to prove he’s got what it takes.

And former Virginia Sen. Jim Webb and Rhode Island Gov. Martin O’Malley are the long shots, trying to break out of the back of the pack.

TIME spoke with speech consultant Ruth Sherman, who works with candidates, business executives and celebrities, to get some tips on what each of the candidates needed to do Tuesday to set themselves apart. Here’s her advice.

Read next: How to Watch the Democratic Debate Online for Free

The Frontrunner: Hillary Clinton

Who is she: Former Secretary of State, U.S. Senator from New York and First Lady

Where she stands: 46 percent, in the most recent CBS News poll

What she should do: Clinton has to help the audience visualize her in the Oval Office while getting past a long-running email scandal. Sherman says Clinton will have to avoid some of her speaking flaws, such as dropping eye contact when thinking and raising her volume when passionate. “She has to connect on an emotional level with voters,” said Sherman. “She, above all, must look and someone who cares very much about the struggles voters are encountering.”

The Challenger: Bernie Sanders

Who is he: Current U.S. Senator from Vermont, former U.S. Representative from Vermont and Burlington mayor

Where he stands: 27 percent, CBS

What he should do: Sanders served in Congress since 1991, a record he should tout for proof of experience—since he isn’t practicing for the debate. Sherman says that for Sanders, a lack of preparation is a mistake, because the outsider candidate should be looking to perform well here and preparation is key to projecting confidence. Of his speaking style she offered: “He seems grumpy and curmudgeonly. We don’t elect grumpy curmudgeons to office. He should have something ready that people can laugh at.”

The Underdog: Martin O’Malley

Who is he: Former Governor of Maryland, Mayor of Baltimore

Where he stands: 0 percent, CBS

What he should do: This debate will be do-or-die for O’Malley’s campaign, as his poll numbers are dismal. However, he has the most to gain and Tuesday will be a great opportunity to get on everyone’s radar, with a chance to connect on domestic issues as a former Governor and Mayor. “He’s a good presenter, looks the part, so it’s easy for people to imagine him as president,” said Sherman.

The Longshot: Jim Webb

Who is he: Former U.S. Senator from Virginia, Secretary of the Navy

Where he stands: 2 percent, CBS

What he should do: Webb, according to our speech expert, is not a good speaker. He will have to introudce himself to many in the audience who are unfamiliar with him. Webb does have a strong military background to reference and add context to international issues for the audience. “When he says he voted against the Iraq war, you believe he knows something about it the others don’t,” said Sherman.

The Longshot: Lincoln Chafee

Who is he: Former Governor of Rhode Island, U.S. Senator from Rhode Island

Where he stands: 0 percent, CBS

What he should do: As a relative unknown in the race, Chafee must introduce himself to the Democratic Party at-large or risk an early exit. Though he entered politics as a republican, Chafee came around in 2007 and has valuable insight to offer on the GOP. However, Sherman believes that Chafee smiles too much, which could make him appear somewhat timid, which he isn’t. “If the way you look and sound contradicts what you say, people will believe the way you look and sound and not what you say,” said Sherman.