The Constitution appears to be having a moment.

When Khizr Khan, the Harvard-educated lawyer and father of a Muslim soldier killed in Iraq, chastised Donald J. Trump at the Democratic National Convention last week, he made his point with a small, but deeply symbolic prop.

“Let me ask you,” said Mr. Khan, directly addressing the Republican presidential nominee, “have you even read the United States Constitution?”

As the audience erupted in cheers, Mr. Khan pulled a miniature version of the founding document from his coat pocket and shook it in the air. “I will gladly lend you my copy,” he said.

It was a star turn for the Constitution that stirred the hearts of dozens of organizations across the country dedicated to promoting its tenets.