ARLINGTON, Va. — It wasn’t even noon today at Arlington National Cemetery as Maine Gov. Paul LePage and first lady Ann LePage prepared to lay a wreath at the mast of the USS Maine in honor of those who went down with the ship off Cuba in 1898.

But Wayne Hanson, chairman of Maine-based Wreaths Across America, looked out from the mast monument in wonder at the sea of green wreaths with red bows gently resting against rows of white gravestones.

Because with the help of more than 15,000 volunteers, the nonprofit group already had placed on service members’ graves most of the estimated 85,000 to 90,000 wreaths carried into the cemetery by a convoy of trucks.

The day marked the 20th anniversary of the first year that Karen and Morrill Worcester used wreaths from their Harrington-based Worcester Wreath Co. to honor veterans.

The effort started with 5,000 wreaths and has been growing exponentially in recent years, especially after the launch in 2007 of Wreaths Across America, which gathers donations and coordinates the work of supporters and volunteers in an effort to expand the scope of the wreath-laying.

“It’s amazing what we’ve done,” Hanson, a Maine native who lives in the Washington area, told volunteers gathered around the USS Maine mast. “I thank you. Maybe next year we can do the whole cemetery” of some 220,000 grave sites.

Earlier this morning, as the Republican LePage placed a wreath on the grave marker of a soldier from the Vietnam era, he looked around and saw thousands of other people busy at work similarly honoring America’s fallen veterans. “It just amazes me that so many (service members) here have given their all,” LePage said.

Sen. Olympia Snowe, R-Maine, also participated in Saturday’s ceremony. Snowe laid a wreath at the grave of Sen. Edmund S. Muskie, D-Maine, who shares a final resting place at Arlington with his family. Muskie was a lieutenant in the Navy.

“This is really something,” Snowe said of the event. “What a remarkable legacy that Morrill and Karen Worcester have bequeathed to future generations.”

The Worcesters started the effort with 13 volunteers in 1992, but it has blossomed into an international movement.

Volunteers today put about 325,000 wreaths in 740 American cemeteries and 25 cemeteries abroad, including in Afghanistan, to honor American troops.

“It isn’t a sad occasion here. We are celebrating their lives,” said Karen Worcester, Wreaths Across America’s executive director.

Said Morrill Worcester about the throngs at Arlington today to help with that celebration: “It is a testament that so many people feel the way we do.”

People of all ages attended today’s event at Arlington National Cemetery. Chris Susco, 12, of Clifton, Va., said he appreciated that, “We have people willing to go to do the will of our country.”

Linda Conard, 71, came in from Ohio with her 12-year-old granddaughter Carly Grace Moyer for the day of honor. Her 85-year-old husband, Donald, didn’t make the trip, but she laid a wreath at the grave of one of his World War II shipmates who died three years ago. “I just thought this was something that I had to do, to honor other veterans,” Conard said.