Washington (CNN) -- It's become a moving holiday tradition to honor the nation's war dead.
But now, donations may be falling short as thousands of graves could go without a wreath decorating their headstones ahead of the holidays in Arlington National Cemetery.
While the ultimate goal is to cover every gravestone in Arlington, organizers last year covered about one-third with wreaths. But volunteers always make sure to cover Section 60, the area of the cemetery with soldiers from the wars in Iraq and Afghanistan.
"And behind every one of those grave markers is a story. There's a family who has grieved," Wayne Hanson of "Wreaths Across America" said.
This year's deficit isn't so much from a lack of donations for the wreaths but more likely because donors are trying to spread the Christmas spirit to other veteran's cemeteries across the country.
Still, that's leaving the organization over $500,000 short of their fund-raising goal. That translates to about 35,000 fewer wreaths to be laid in Arlington this year.
Each wreath costs about $15 to make. They're made by the Worcester Wreath Co. in Maine and then trucked down to Arlington where they're fixed to the graves.
Hanson, president of the group's board of directors, said while he's happy the tradition is spreading to other places, Arlington is what he considers America's national cemetery with veterans from every conflict and across the country buried there.
The practice started in 1992 when Worcester donated some 5,000 wreaths. Things really exploded about a decade ago when word of the wreath laying spread.
Last year, more than 400,000 wreaths were donated -- 100,000 to Arlington alone -- and placed at cemeteries in all 50 states.
Volunteers are planning to lay the wreaths on December 14, but Hanson said there's still time to donate and there will be empty trucks waiting for last-minute donations, right up until the day before.
People, groups or businesses can donate or sign up to volunteer at the organization's website.
"We will never forget the people at rest in Arlington," Hanson said. "We want to go forward (with the donations) not backward."