Matthew Phelps as he proposes to Ben Schock Saturday night at the White House. (Photo courtesy of Jennifer Cintron)

It might not be the first, but the same -sex marriage proposal that happened Saturday night at the White House is the first to go viral.

Within minutes, a picture of Matthew Phelps and Ben Schock was posted by a bystander. Phelps posted his own photos Sunday on Facebook; by Monday they were everywhere.

“It wasn’t something we were trying to do,” Phelps told us Monday. “I just wanted to make a special night for Ben.”

Phelps, a 35-year-old Marine captain, and Schock, a 26-year-old nursing student, were celebrating their six-month anniversary with a holiday tour of the White House decorations. They met two years ago, but didn’t start dating until this past summer, when Phelps took Schock to a LGBT Pride Month reception at the White House. Last month, Phelps was offered tickets for the White House tour with the Military Partners and Families Coalition and hatched a plan.

He got one of his friends to carry the engagement ring into the mansion Saturday so Schock wouldn’t see it when they emptied their pockets to go through security. Smart! Who thinks of that? “I’m a logistics officer,” explained Phelps, who served in Iraq and attends the Marine Corps University in Quantico.

With the ring back in his own pocket, he toured the place with Schock. They stopped to pose for a photo near the Blue Room — and that’s when Phelps dropped to one knee.

A surprised Schock said yes — though Phelps was so sure of the answer that he had already arranged for friends to celebrate with them after the tour: “I am a Marine. Over-confident is what we do.”

The couple, who live in D.C., are planning a spring wedding.

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