Ken Kragen, president of USA for Africa, clutched just a few of the 70,000 letters that have poured in to the Los Angeles foundation since the March 7 release of the multi-superstar recording of "We Are the World."

At the foundation's reception on Capitol Hill last night, he mentioned a few of the contributions:

* $76, representing the entire savings of a 4 1/2-year-old Colorado girl who had asked her parents to "send all her money before any more people died."

* A family's last food stamp dollar sent because "Mom and I know what it is to be hungry . . . may God bless all of you and save the babies."

* The last and only dollar of a death-row inmate in Alabama's Huntsville State Prison.

* A $250 child-support check turned over to USA for Africa.

* A letter from one bride's mother saying that wedding guests had been asked to send donations to USA for Africa in lieu of wedding gifts.

And then there was the note that brought a sigh and some tears to several hundred people packed in a hearing room at the Dirksen Senate Office Building. "I heard a young man recently speak of his screaming at God for allowing children to starve . . . until he realized the starving children were God screaming at him."

Such letters and donations, and the tremendous sales of the "We Are the World" single and album, have helped USA for Africa raise $45 million in just nine weeks, Kragen said, adding that it has been "the greatest outpouring of public support for a charity of this nature in history."

The money will be going to combat the drought-driven epidemic of starvation and infant mortality that affects 34 sub-Saharan African countries, most notably Ethiopia.

Last night, the Recording Industry Association of America sponsored the Capitol Hill reception that featured brief speeches from Kragen, USA for Africa's chief organizer; "We Are the World's" cowriter and pop star Lionel Richie; and RIAA head Stanley Gortikov. There was also a moving compilation of clips from network, local and cable television and a screening of the recent hour-long HBO special on the making of "We Are the World," the highest rated program in HBO history.

Among the politicians in attendance were Rep. Mickey Leland (D-Tex.), chairman of the Select Committee on Hunger ("everybody is very excited about what they have done," he reported); Sens. Strom Thurmond (R-S.C.) and Larry Pressler (R-S.D.), and Reps. Henry Waxman (D-Calif.), Bill Lowery (R-Calif.) and Benjamin Gilman (R-N.Y.). Many senators who had been expected at the reception were tied up in the voting on the foreign aid authorization bill.

"We are making a difference," said Richie, echoing many of the lines from the song that he wrote with Michael Jackson. "The world is now awake, alive and breathing the words 'we are the world.' There are children who are going to be thankful that we've gathered here to figure out what we can do to save their lives."

Yesterday's gathering also marked the first meeting of the distinguished medical task force assembled and headed by pediatrician and medical professor Dr. Irwin E. Redlener. Among its members are Dr. Rose Gibbs, former chief of medical operations for the Peace Corps from 1979 to 1984; Dr. Larry Brown, chairman of the Physician Task Force on Hunger in America; Dr. Robert J. Haggerty, president of the American Academy of Pediatrics; and Dr. Victor Seidel, president of the American Public Health Association.

"I wanted to put together a medical team that was equal to the group that raised the money," Redlener said.

The task force will "help direct the spending for the medical health areas (about 35 percent of the funds) in a way that's most productive and effective and the most bang is gotten for every dollar." Redlener, Kragen, Harry Belafonte and several other representatives of USA for Africa will be flying to Ethiopia in June to begin planning distribution channels