SAN FRANCISCO — The U.S. won’t elect a president until next year but the debate over the crowded field of candidates jostling for the Oval Office emerged as the hottest topic on Facebook this year.

The race for the Democratic and Republican party nominations eclipsed an outpouring of emotions over deadly attacks, strife, social issues and disasters.

The rankings released Wednesday open a window into the cultural mindset by analyzing how frequently specific high-profile events, politicians, entertainers, athletes, movies and TV shows were mentioned in the posts of Facebook’s 1.5 billion users.

“This year, the most talked about global topics reflected the serious challenges people are facing all over the world — and how our global community is connecting and coming together in ways we have never seen before,” said Sheryl Sandberg, Facebook Inc.’s chief operating officer.