Former President Barack Obama and Michelle Obama on Tuesday called on the nation to embrace Kamala Harris in urgent messages to the Democratic National Convention that were at times both hopeful and ominous.

But a moment of the former president’s speech caught the internet’s attention and continues to make its rounds.

Obama: “The people who will decide this election are asking a very simple question, who will fight for me? Who’s thinking about my future? About my children’s future? About our future together? One thing is thing is for certain, Donald Trump is not losing sleep over that question. Here’s a 78-year-old billionaire who has not stopped whining about his problems since he rode down his golden escalator nine years ago. It has been a constant stream of gripes and grievances that’s actually been getting worse now that he’s afraid of losing to Kamala.”

He added: “There’s the childish nicknames. The crazy conspiracy theories. This weird obsession with crowd sizes. It just goes on and on.”

Barack Obama made a gesture with his hands and looked down at them after he delivered the “weird obsessions with crowd sizes” line, drawing laughs from the audience.

Obama, the first Black president in U.S. history, insisted the nation is ready to elect Harris, who is of Jamaican and Indian heritage and would be the nation’s first female president.

The fiery messages from two of the Democratic Party’s biggest stars underscored the urgency of the moment as Harris works to stitch together a broad coalition in her bid to defeat Trump this fall.

The vice president is drawing on stars like the Obamas and other celebrities, officials from the far left to the middle, and even some Republicans to boost her campaign.

And while the theme of the night was “a bold vision for America’s future,” the disparate factions of Harris’ evolving coalition demonstrated, above all, that they are connected by a deep desire to prevent a second Trump presidency.

The Associated Press contributed to this report.