When María Corina Machado unexpectedly appeared at a Catholic church in western Venezuela on Sunday morning, worshippers erupted in applause. Some embraced her and burst into tears. Others handed her rosaries or began singing the national anthem.

After nearly a year in exile, the opposition leader was home. As she traveled to Caracas, hundreds of miles away, supporters lined highways and crowded town squares to welcome her.

It was a striking contrast to the circumstances of her departure just 10 months earlier.

Back then, Ms. Machado was living in hiding, moving between safe houses to evade arrest after leading a movement that challenged Nicolás Maduro’s claim of victory in Venezuela’s disputed 2024 presidential election. She eventually slipped out of the country in secret to receive the Nobel Peace Prize in Norway.

Now, Mr. Maduro is in a Brooklyn jail cell. His former vice president, Delcy Rodríguez, leads the government as acting president. Hundreds of political prisoners have been released.…