Donald Trump s children and his wife will speak at the Republican National Convention this week, a standard move by modern campaigns intended to soften the candidates image. According to the official RNC schedule , Mr. Trumps sons Eric and Donald Jr. will appear on Tuesday and Wednesday and are expected to address topics ranging from the Second Amendment to Benghazi. Trumps daughter Ivanka will occupy a prime Thursday slotperhaps even the principal task of introducing the partys nomineewhile Melania Trump may be presented as a modern-day Jacqueline Kennedy when she takes the stage this evening.

No matter what role in the speaking lineup has been reserved for Mrs. Trump, her speech may be more consequential than the remarks of any family member or surrogate. Unlike Trumps children, close family friends, or professional allies, Melania is uniquely positioned to describe the reasons she chose Donald Trump as a life partner. There is no stronger assertion to be made regarding a candidates character than that coming from a spouse, if the spouse can pull it off authentically.

Survey experiments in my new book, On Behalf of the President , demonstrate that spouses are more effective messengers than vice presidents and presidents themselves when it comes to questions of the presidents honesty, morality, compassion, and relatability. My most recent research shows that Bill Clinton and Melania Trump are both capable of boosting opinion of their spouses in this manner, particularly among political independents and members of the opposite partygroups which Trump has seemingly gone out of his way to alienate with remarks and gestures that many have deemed racist , sexist , ableist , anti-POW , anti-Muslim , and anti-Semitic . If Melania follows the core patterns that the convention speeches of spouses have featured for 20 years, she may have a chance to temporarily suspend Trumps plummeting popularity, perhaps making up some of the ground he has lost among women and minorities .

Spouses of non-incumbent presidential candidates have not been addressing conventions for very long. Eleanor Roosevelt was the first incumbent presidential spouse to deliver a national convention speech in 1940, and it wasnt until 1972 that another incumbent spouse, Pat Nixon, would follow suit, becoming the first Republican incumbent spouse to deliver a national convention speech. In 1996, Elizabeth Dole became the first non-incumbent spouse of a presidential candidate to address a national convention, a practice that would continue in every election year thereafter as the primary vehicle through which campaigns attempt to humanize the candidates.

In 2012, both Ann Romney and Michelle Obama used the convention as an opportunity to frame their husbands in a way no other surrogate could: from the perspective of a young idealistic couple who began their marriage with modest surroundings, as parents who worked hard to provide for their kids and worried about their wellbeing, and as descendants of families who passed down the same values the Romneys and the Obamas imparted to their children.

For Melania, accomplishing the feat of relatability will be much tougher; after all, she is a former high-fashion model married to a billionaire who has the highest unfavorable ratings of any presidential nominee recorded in history. But she is the Trump surrogate best positioned to take a shot at it. If Melania follows in the footsteps of her predecessors, here are some of the points she will likely make.

Im just like you. Melania will make the case that she has experienced the personal and professional obstacles that most Americans share. It is an argument that Trumps children probably cannot make convincingly. She will share the story of her upbringing in Slovenia, her experience emigrating to the United States and learning English, and starting her career as a teenager in a highly competitive industryone that is fraught with many of the same impediments to success and discrimination towards women as any other businesswith no connections or financial assistance. She will emphasize that motherhood is the most important part of her identity, and mention the complications of balancing work and home and making time for everyone in a big, blended family. And she will say it all with the humility of an outsider, a person who has little experience with public speaking and little interest in partisan politics, but who will go to uncomfortable and unfamiliar lengths to support a person she loves who has supported her all along.

Donald Trump is just like us. Melania will then propose that Donald Trump shares the same priorities of self-reliance, success through risk-taking, hard work, and love of country that she and many Americans value, despite having a very different background. She will tell the audience that it is one of the reasons she fell in love with him. She will say that that Donald Trump has suffered loss and overcome challenges, and that he cares about struggling families just as much as he cares for his own. She will testify that he helps disadvantaged people and communities and describe how he interacts with his family and his colleagues away from the cameras. She will describe how Donald Trump settles differences in opinion and forms unlikely coalitions.

Donald Trump will be a great president. Melania will make the concluding case that the character attributes her husband possesses make him a good leader. She will argue that what makes Trump a superb businessman, father, husband, and neighbor are the same traits presidents must have.

These are the things Mrs. Trump will say if she plans to make the same emotional appeal to voters that candidate spouses have made in the past. Then again, the Trump campaign has never heeded the traditional campaign playbook.