What Clinton's Historic Speech Needs to Accomplish

PHILADELPHIA, Penn. -- The history-making nature of this week has not gone unnoticed at the Democratic National Convention, but the most pivotal moment comes tonight when Hillary Clinton addresses the convention and formally accepts her party's nomination for president.

Few specifics about the speech have been released in advance but some aides have given some insight into the address.

Campaign Manager Robby Mook said that she will "weave" the themes that have been touted throughout the convention, which has focused on how America is "United Together" and "Working Together" while Clinton has had "A Lifetime of Fighting for Children and Families." Tonight's theme -- "Stronger Together" -- has been a regular maxim of her campaign.

"Tonight in her speech Hillary is going to stitch together each of these themes and talk about how this election is really a moment of reckoning for the voters," Mook said at a briefing this morning.

John Podesta, another Clinton campaign manager, told ABC News today that Clinton's speech tonight will draw on her experiences and the people she has met. She'll then segue into what she wants to achieve during her presidency.

Podesta said that the speech will also include a couple of good jabs at her Republican rival, Donald Trump, but noted that it would be in keeping with the line coined by First Lady Michelle Obama during her Monday speech, when she said, "When they go low, we go high."

Clinton sought ideas for this speech from some of her former speechwriters and senior policy adviser Jake Sullivan, but it was Dan Schwerin, Clinton's current head speechwriter, who took the lead.

James Campbell, a professor of political science at the University at Buffalo who has written a book about political polarization, said that in addition to "lighting into Trump," there are two other topics she should be sure to include: an appeal to supporters of Bernie Sanders, and an acknowledgement of her own shortcomings.

"She should reassure them that she has heard them and their concerns and that she will be a tireless advocate" for causes that were important to the Sanders campaign, Campbell told ABC News.

"She must not only unify the party, but excite it -- invigorate it," he added.

When it comes to her shortcomings, Campbell says there is a way to turn them into advantages.

"Everyone knows that she has a great deal of experience, but they also know that she has left a long trail of controversies in her wake," he said.

"She should emphasize that her experience is not just a series of entries on her resume, but that she has learned about policy and about her own strengths and weaknesses through this experience. Experience is not a virtue on its own, but it is an opportunity to learn," he said.

Tonight won't be Clinton's first appearance at the convention -- she made a video address to the group on Tuesday after her husband's speech and then she walked on stage to thank President Obama after his speech last night -- but it will be the first time she formally addresses the crowd in person.

While the bar is undeniably high for Clinton tonight given the string of speeches that have already been given this week, Campbell doesn't think that she will be held to the same standards.

"I do not think expectations for her speech are at the Obama, Biden and Bill Clinton level," he said.

ABC News' Ann Compton, Liz Kreutz, Alana Abramson and Corinne Cathcart contributed to this report.