Undated (AP) _ Volunteers warmed the lives of the sick, poor and homeless Tuesday as Christmas gave Americans a merry break from wallet-watching and war wariness.

''I cannot change the world, but I know for a fact I can make a difference,'' said Iqbal Emamudeen of Orange, N.J. A publicist for a chain of drug stores, he was among about 135 volunteers serving Christmas lunch for hundreds of homeless and needy people at a church agency in downtown Newark.

Volunteers led by civil rights veteran Hosea Williams fed an estimated 30,000 people in Atlanta. In New York, 1,500 people ate stuffing, sweet potatoes, succotash and pies at a hotel as fourth-and fifth-graders sang carols.

Impoverished thousands were served a traditional holiday feast at Los Angeles' Skid Row while jail inmates nearby were blessed during a dawn Mass celebrated by Archbishop Roger Mahony.

In the Christmas spirit of giving, a Santa in Kansas City, Mo., donated blood. Singer James Brown offered soul for soldiers whose holiday leaves were canceled. Adoptive parents in Texas gave their hearts to two infants rescued from the squalor of a Romanian orphanage.

Americans around the Great Lakes enjoyed a white Christmas, but retailers were blue and the holiday left some newly jobless Americans in the red.

Some merchants reported a last-minute surge of gift-buying by consumers who had seemed intent on cutting back spending. But receipts were not expected to make up for disappointing early sales.

''It's not going to be anything that's going to excite anybody,'' said Kenneth Macke, chairman of Dayton Hudson Corp.

Some charitable organizations in the Northeast blame the economic downturn and government cutbacks for a doubling in the demand for services. But in New Hampshire, food bank organizers said charity was keeping pace.

''The donations have picked up tremendously,'' said Thomas Murphy, volunteer administrator of the Monadnock Area Food Bank in Peterborough, N.H.

Ham radio operators donated their time to connect sailors and Marines on ships in the Middle East with their families. Guy Titman of Charlotte, N.C., said he had made about 70 connections by noon.

''Most of the conversations are: 'Merry Christmas. We miss you. We love you,''' he said.

Xavier Fernandes opted for a more humorous greeting to his son Roman, a Marine corporal in Saudi Arabia.

''I know it's rough over there,'' Fernandes said on a TV satellite hookup from a Boston hotel. ''But look at it this way - at least you don't have to see the Patriots' games over here.'' The New England Patriots are 1-14, the National Football League's worst record.

Cardinal Joseph Bernardin and the Rev. Jesse Jackson held separate Christmas services for prisoners at Chicago's Cook County Jail.

The Rev. Tyrone Crider of Operation PUSH, who joined Jackson, told inmates in the jail's gymnasium about the best gift they could receive.

''It fits all sizes; it doesn't go out of style and best of all, God's gift comes with all accessories included in his son Jesus Christ.''

James Brown, the singer serving a prison term in South Carolina for assault, was allowed to give his first public performance in two years, a benefit for 4,000 soldiers at Fort Jackson, S.C.

Brown sang four songs for the troops, shouting ''Merry Christmas'' between numbers. He wrapped up the set with ''God Bless America'' as trainees in crew cuts clapped and cheered.

The Florida Baptist Ministries sent turkeys to the 28 hungry crewmen of the Itapage, a Brazilian ship stranded in Jacksonville since federal marshals seized it for debts on Dec. 3.

Stacey and Ben Disney of Dublin, Texas, gave their 11-month-old son and 7- month-old daughter a gift they may not appreciate for several years - a scrapbook detailing how their adoption rescued them from the squalor of a Romanian orphanage.

Ray Shick, dressed as St. Nick, arrived Christmas Eve at the Community Blood Center of Greater Kansas City. Instead of passing out toys, Santa gave his 50th pint of blood.

American Ice owner Robert Pierce donated three tons of shaved ice to make snow on the lawn of Elaine Riddle, of Dallas, who has lymphatic cancer.

''I told my friend Kathy that if I had one last Christmas, I wanted it to be a white one,'' Ms. Riddle said. ''I'm 41 years old, and I've never had a white Christmas - until today,'' she said.

Weather across the nation was more arctic than scenic, but lights twinkled through freezing rain and sleet.

Nancy Cole of Lewisburg, Tenn., vowed not to take down her decorations until her husband, National Guard Sgt. William Ray Cole, comes home from Saudi Arabia.

''I'm going to buy him a gift a week till he gets back home,'' Mrs. Cole said. ''I hope he's not gone too long.''

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