For almost 30 minutes tonight, Elizabeth Natoli, a 61-year-old widow from Greenbelt, Md., sat in a hot TV Studio here, smiling sweetly and looking for all the world like she was about to enjoy afternoon tea.

A moment later, she was the winner of $1 million in the 15th drawing of the Maryland state million-dollar lottery-still calm, still smiling sweetly and driving the TV show producer crazy.

From the winner came no cries or tears of joy, and the producer had to depend on six relatives who dashed on stage to provide the hoopla, excitement and tears.

Nine other persons, each with a contingent of supporters in the WBAL-TV studio, had sat through an agonizing elimination only to see their dreams of a million dollars - $50,000 a year for 20 years-disappear.

A widow for six years and a resident of Greenbelt since moving here from New Jersey in 1973, Natoli said she had no major plans for her windfall, except, "I want to help a lot of people."

Natoli lives with his sister, Mae Schossler, who bought the winning ticket last year. The family buys two 50-cent tickets each week and, despite winning, is going to keep playing, they said.

Before the drawing, Natoli said she had had "a very letdown feeling"-expecting to lose and disappoint her nephews and nieces whom she has promised to help with school expenses.

Afterwards, Natoli said she simply wanted to go out to dinner last night.

"We were going to McDonalds," a jubilant great niece said, "but not anymore."

While reporters gathered around the winner, the other contestants were leaving quietly. Seven of them were given $5,000 for being finalists, one got a $10,000 check for being third, and the runnerup, William Fauntleroy of Easton, Md., picked up $100,000.

Off to the side, smartly dressed in black, sat a 1978 million-dollar winner, Laurene Browne of Southeast Washington. Asked for advice that she would offer the winner, Browne replied, "Be careful, 'cause the IRS will really tie you up."

Last night's 10 finalists were chosen two weeks ago from a pool of 358 persons who had bought winning tickets to qualify.

The finalists were given numbers by lot and were eliminated one by one as their numbers were flashed on a screen behind them. In a twist on picking a lucky number, the winner of the million dollars is the person whose number doesn't come up before the other contestants.

Natoli's sister Mae also won something last night-a promise from her new millionair relative that she could quit her job with a local insurance company. Mae smiled sweetly. But, unlike her sister, she kicked up her heels and said, "Let's go celebrate." CAPTION: Picture, Lottery chairman George P. Mahoney and Elizabeth Natoli show off check.