CONCORD, N.H. -- When Paul E. Tsongas finished speaking at St. Paul's School the other day, Priscilla Clark wanted to hear more.

"I don't think I've been so excited about a candidate since Stevenson. I think he's marvelous, and I think he has wonderful charisma," she said.

Until recently, the former Massachusetts senator was dismissed as a "second tier" candidate who would remind voters of another Greek from that state, 1988 Democratic nominee Michael S. Dukakis. Now he has climbed to second place in the polls, putting him in position to succeed front-runner Bill Clinton should he falter before the New Hampshire primary Feb. 18.

Mr. Tsongas, who is scheduled to speak at 1 p.m. today at the University of Maryland College Park, has been winning over voters with a tough, detailed economic message and an appealing personal story about growing up in depressed Lowell, Mass., and overcoming cancer in the 1980s.

Some voters liken him to former Arizona Gov. Bruce Babbitt, a 1988 Democratic presidential candidate who dared to speak frankly; to an older voter like Mrs. Clark, he evokes the late Adlai Stevenson, the intellectual Democratic nominee in 1952 and 1956.

But charisma? You're going too far, Mrs. Clark. Nobody, not even the candidate himself, describes Mr. Tsongas as charismatic.

One problem is his wispy voice: It threatens to crack under the weight of his ideas.

He often breaks eye contact, averting his gaze like a shy teen-ager at a school dance. Were it not for dark, bushy eyebrows, his face would frustrate caricaturists.

But he has improved his public appearances with the help of a communications coach.

At St. Paul's, he began slowly, listening to the crowd titter when someone mispronounced his name (it's SON-gus). He moved out from behind the lectern, took the microphone in his hand and gradually reeled in his audience with scriptless talk about what America needs, digressions into his background, and humor.

Mort Sahl he wasn't, but an audience of several hundred students, staff and spouses vigorously applauded.

"I wanted to make sure he was able to project his ideas successfully, and he really does," said music teacher Kathryn Southworth.

It is his economic ideas that make people pay attention.

In contrast to the skimpier economic menus of his opponents, Mr. Tsongas offers an all-you-can-eat buffet. "A Call to Economic Arms," the manifesto he autographs at campaign appearances, runs 86 pages. It rejects the tax-cut and Japan-bashing approaches of other candidates in favor of a multiyear program for stimulating manufacturing.

Without a strong manufacturing base, he warns, America can't cure its economic or social ills. "My view is if you bring the engine back, the rest will take care of itself."

He denies that manufacturing decline is inevitable as other countries industrialize. While the percentage of the U.S. work force involved in manufacturing has decreased from 30 percent to 16 percent since 1960, he says, "If you look at Japan, their percentage . . . has remained the same.

"How do they do it? As one business dies, another is created."

He would seed industrial development with capital gains tax cuts -- offset with increased income taxes on the rich -- and use government contracts to induce companies to adopt future-oriented strategies. Toward this end, he proposes eliminating quarterly earnings reports and changing liability laws that now compel corporate directors to maximize short-term stockholder returns.

Mr. Tsongas scolds both parties, telling Democrats that they shouldn't be anti-business and Republicans that there needs to be a national industrial policy.

To critics who say he has forsaken his liberal roots, Mr. Tsongas, 50, reminds them that he was a JFK-inspired Peace Corps volunteer in Ethiopia and an early supporter of civil, gay and abortion rights.

"A liberal is someone who can expand the economic pie," he said. "If you can't expand the economic pie, you're not a liberal."

He didn't develop his ideas in a vacuum, and he didn't come by them yesterday, he tells voters.

His immigrant father, Efthemios Tsongas, ran a dry cleaners in Lowell, "12 hours a day, six days a week, 51 weeks a year. By any fair standard, this workload should have brought him a fair reward. It didn't.

"Industry was leaving the city, and no matter how hard he worked, the forces of Lowell's economic decline were too much to overcome."

Mr. Tsongas launched his political career in Lowell, moving up from the city council to Congress and, in 1979, the U.S. Senate. But he was diagnosed with lymphoma in 1983 and gave up probable re-election to fight it.

As he grew healthier, he practiced law and dived into the business world as a member of several corporate boards. He often cites his "private sector" experience to authenticate his economic credentials.

He refers repeatedly to his close call with cancer, which required bone marrow transplants and radiation to treat, suggesting that it focused him on the future.

"What I'm doing is not just ambition," he said at St. Paul's. "This country is in trouble, real trouble. And someday there's a judgment upon us: What did you do? What did you do?" he said, pausing. "That's where I'm coming from."

People applaud, and later laugh, as Mr. Tsongas slips in humorous digs at President Bush.

He derides the president as the "beggar-in-chief" for his recent trade trip to Japan, and mocks him for his Christmas shopping venture in Frederick, Md., to buy socks.

The economy is Mr. Tsongas' hole card. As it grew worse, people began to take him more seriously, looking for specific answers. He jokes about the time last spring when Mr. Bush was riding high in the polls, and he was the only Democrat running.

"I got into this race when George Bush was at 91 percent," he said. "You can see what damage I've done to him."

Despite his rise in the polls, Mr. Tsongas hasn't been able to raise the money and build the organization he will need elsewhere. He is counting on a strong finish here to attract both funds and publicity.