Beto O’Rourke, the charismatic Texas Democrat and former member of the House of Representatives, announced his presidential campaign in a video on Thursday. The three-minute clip quickly racked up thousands of shares, with some viewers excited by the prospect of his out-of-nowhere political rise. But others were put off by how his campaign deployed an age-old trope in American political theater — the silent, supportive wife.

Throughout the video, Mr. O’Rourke’s wife, Amy, sat quietly by her husband’s side, periodically grasping his hand as he outlined his campaign vision.

She occasionally smiled. And gazed.