To the political strategy that might in the future be called “transparent efforts to change the narrative and repair the damage done to Joe Biden in the first presidential debate,” add the dress that Jill Biden wore to accompany her husband to his next-day rally in Raleigh, N.C.

As President Biden attempted to address some of the concerns about his age and energy on Friday, his wife, a political spouse who often seems to choose clothes that recede into the background, took her place by his side in a navy blue crepe dress plastered with one word over and over again: “Vote.”

Given the many post-debate reaction stories that focused on viewers’ anxious feelings about Mr. Biden’s shaky performance, that could not have been a coincidence.

Especially given the fact that Dr. Biden has often seemed reluctant to engage in the game known as first lady fashion diplomacy, largely wearing clothes by designers she feels comfortable with rather than ones with any obvious tactical connection to an event. For her to choose a dress so guaranteed to call attention to itself, and to do so at a time when any attention that is not about her husband’s age is probably good attention, is a statement in itself.

After all, there could be no doubting that all eyes would be on the president in his first rally after the debate, in part to judge whether his weak showing the night before would be repeated. Or that the pictures of that rally would be disseminated far and wide. And that, as a result, what his wife wore, as with every detail of his performance, would send a signal not just to the general audience, but also to the political pundit class that has been calling for Mr. Biden to step aside. The one that has noted that the key influencer would be his wife.

He might have been speechifying, but that dress did the talking.

It was by Christian Siriano, a designer known for his inclusive approach to fashion and who created the iconic blue dress Michelle Obama wore at the 2016 Democratic convention. In an email, Mr. Siriano said the first lady’s team had reached out to him about a month ago to request a new version of a “vote” dress he had made for his spring 2021 collection.

Rebecca Feinglos, the founder of @grieveleave, a grief support platform, said she was wearing one of the original Siriano “vote” dresses when she met Dr. Biden at an event a few months ago. The first lady “asked me where I got my dress,” Ms. Feinglos wrote in an Instagram post, “and I was so excited to tell her its story.”

Mr. Siriano said that when Dr. Biden’s team called, he “came up with this shape that felt classic but modern and hopefully tasteful for this event today.”

He added, “I think we all knew after the first debate that it was going to be an important one that could send a message to the world.”

This is the third time in the last four years that Dr. Biden has worn a garment with a message written atop it.

In 2020, before the last presidential election, Dr. Biden wore a pair of Stuart Weitzman knee-high boots that also read “vote.” And in 2021, at the first Group of 7 meeting in Britain after the president took office, she wore a jacket with the word “love” on the back. The choice was widely interpreted as a riposte to the jacket Melania Trump notoriously wore during her husband’s administration with the words “I Really Don’t Care, Do U?” scrawled on the back.

Now the matchup is back, and so are words on clothing. It is, perhaps, only to be expected. Dr. Biden is an English teacher. She knows exactly how much succinct language matters — even if it is on a dress.