WATCH: Nurse sings ‘Amazing Grace’ at national COVID remembrance

On the same day that the estimated coronavirus death toll surpassed 400,000 lives lost in the U.S., President-elect Joe Biden, Vice President-elect Kamala Harris and their spouses visited a somber national memorial at the Lincoln Memorial in honor of the victims.

With the Reflecting Pool as a backdrop, and 400 lights lit up in honor of the 400,000 dead, Lori Marie Key, a 29-year-old nurse from Livonia, Michigan, sang “Amazing Grace.”

READ MORE: How communities across the country are honoring COVID victims

Key once sang the hymn during a shift change at St. Mary Mercy Hospital, which was captured on a video that went viral. She said it’s been heartbreaking to work at her hospital’s COVID unit.

“But when I am at work, I sing,” she said. “It gives me strength during difficult times, and I believe it helps heal.”

Biden delivered brief remarks after Key’s performance, saying that: “To heal, we must remember. It’s hard sometimes to remember. But that’s how we heal. It’s important to do that as a nation.”

Harris’ message to the nation was that her “abiding prayer is that we emerge from this ordeal with a new wisdom, to cherish simple moments, to imagine new possibilities, and to open our hearts, just a little bit more, to one another.”