Pam Shriver, the honorary chairwoman for the Maryland committee to relect President Reagan, had a dream the other night. "I dreamed I saw Reagan and I said, 'I'm working for you in Maryland but what do I tell them about the deficit?'

"Martina (Navratilova) was there and she was going like this to the president," Shriver said, yanking on a friend's sleeve. "And she's saying, 'What about the environmental stuff?' "

Pam Shriver, the tennis player, has a problem. She thinks about more than the game. This can have a deleterious effect on a forehand. In a world in which narrow-mindedness is considered a virtue, Shriver struggles to channel her thoughts. "Most of the people I talk to don't even vote," said Shriver, a distant cousin to Sargent Shriver, the former Democratic vice presidential candidate. "That really bothers me. Most of the tennis players haven't ever registered to vote. My mom worked in the polls on election day since I was a kid. The day I turned 18, I registered to vote."

That was two years after she stunned Navratilova, 7-6, 7-6, in the semifinals of the U.S. Open and introduced the world to her gawky elegance. She was the tall, curly-haired kid with the big serve and the big racket. For seven months in late 1979 and early 1980, her body refused to support her game and her ranking dropped from 11th to 37th. Her shoulder rebelled at the stress she put upon it. It is better. But it will never be the same.

In 1980, she voted for Ronald Reagan and was voted the comeback player of the year. Two years later, on the same court, Shriver came back to haunt her friend and doubles partner, eliminating Navratilova in the quarterfinals. Navratilova cried. Shriver apologized.

Shriver advanced to the quarterfinals today when Sue Mascarin defaulted because of a sprained ankle. If form holds true, Shriver and Navratilova should meet in the semifinals Friday. Shriver is ranked fourth in the world and, because of her serve-and-volley game, is widely considered "the woman who can beat Martina."

"There's two people who carry that name, Hana (Mandlikova) and myself," Shriver said. "I agree. To do it, you've got to play unbelievable stuff. Martina doesn't think she can ever lose to Chris (Evert Lloyd) again. But in her mind, she knows she could lose to Hana or myself on a given day if we are serving well. If I play her, there shouldn't be any pressure. But actually, there will be because I suppposedly could do it."

It's the supposedly that troubles Don Candy, Shriver's coach. "She is more aware of what's she's doing. She believes more in what she's doing. Does she believe wholeheartedly -- I mean in herself? No. Sometimes under some pressure, she doesn't believe enough to go out on a limb where she needs to be to prove it."

Two weeks ago in the third set of the final in Mahwah, N.J., it was 5-5 and 15-30, "Martina missed a first serve and threw in a second ball just anywhere at all and went to the net with her mind tangled in her feet," Candy said. "Pam stood with a bad, bad second serve and did nothing with it and hoped Martina would maybe miss. After the point, she said, 'What have I done?' or more to the point, 'What haven't I done?'

"She must work on this moment. Pam could have broken the game open and hurt Martina mentally. She believed, but not strongly enough to do it, so she joined the ranks of those who aren't quite flamboyant enough and the moment passed."

Shriver believes her moment will come. If you ask what one thing she would like to borrow from someone else to make it happen, she says, "Everyone would like the mental toughness Chris has had over the years. I don't say she's more competitive. But she's more buttoned down, more focused. Because I'm not that way personally, I don't know if that could ever have happened."

It's not that she's scattered, but she thinks about other things: the 1813 townhouse she is restoring in Lutherville, Md., where she grew up, her job as a member of the board of directors of the Women's Tennis Association. Sometimes, she wonders whether a monolithic commitment to tennis might be better for her game. "But I played my best my last two years of high school," she said. "Every second of the day was constructive. When I graduated, there was the biggest void. I was playing 18 tournaments a year and what was I doing? Nothing.

"Tennis can be your whole life and it can still not be enough. To get higher, you have to step it up. To me, Martina is almost sliding back. When I played her in Mahwah, I played okay. I didn't play out of my brain. If I had played out of my brain, I would have won. I played good solid tennis. Last year, if I played good solid tennis, I would take six or seven games. It's funny. She's the first one who made me realize that you can win Wimbledon and the U.S. Open and you're not going to be happy your whole life."

She is 22. It seems she has been around forever, growing up before our eyes. She is, in a sense, the survivor of her generation. Tracy Austin, her contemporary, reached heights Shriver still aspires to, but is burnt out. "If I was going to fall, it would have been when I was 17 or 18," Shriver said. "Now, I'm out of danger except for some really debilitating injury. It just points out how tough it is. When you start, when everything is going great and you're the new kid and you're beating people ranked ahead of you, boy, things are easy. You have no idea. It takes three or four years to realize what you're into."

Candy worries that she is into too many things. This spring, she won three tournaments and moved ahead of Mandlikova to No. 3 in the rankings, a level at which she stayed from February until April. But she kept playing despite an injury to her arm. "Her dedication in Dallas was responsible for her playing through a bad shoulder, bad arm and elbow to the extent where she did nerve damage to them because she felt she was savior of the tournament," he said. "Such dedication is too extravagant for any young player. So from March until well into June, she couldn't play any singles tournaments at all."

Surely, she has improved. The question is how much better can she get? "She's better because she's more consistent," said Billie Jean King. "Her concentration is better. When it gets rough, she doesn't give up. She's on the edge of it. But she's got to learn to come over her backhand, then she can beat Martina."

Mike Estep, Navratilova's coach, said, "She needs to pick up her strength. Her precision is quite effective. But she needs some weight of shot on her serve and volley. She's got to put more meat on her drives."

She is 5 feet 11. "I think honestly if I was three inches shorter, I'd be better," she said.

Her height and reach make her one of the best doubles players in the world -- she and Navratilova completed the doubles Grand Slam at the French Open. But changing directions can be difficult. "There are more things she can do to improve her mobility," Candy said. "Wind sprints and violent, violent practices. She needs to serve better and make more of her opportunites. She has to work more on pivoting, starting and stopping. Her job is to get from there" -- he pointed to the base line -- "to there." He pointed to the net. "It's very difficult to get her to practice it. There is resistance and I don't know why."

Shriver says she no longer worries about being No. 1. "My attitude has changed toward tennis in the last few months because of my house. I sit and think, 'The only reason I have this house is because I'm a hell of a tennis player.' And God, I love it. It has five levels and I built in a loft. One day, I lay in the loft, and I was looking out the two skylights and it was so pretty and I was really just appreciating my tennis. For all the pains and the hassles, God, it gives me so much freedom.

"Every year at the Grand Slam events, people say, 'Well, Pam, is this it for you?' Everything I've done is so gradual. I'm never going to do what Martina's done. I'll never have a record like Chris'. That doesn't bother me. I honestly believe I'm going to get one of these big ones sometime. I figure I've got 10 or 12 more, I'm just talking about Wimbledon and the U.S. Open. I just think my number will come up.

"I could still get so much better. I can improve to the point where I can always be a threat. That's where I belong: always being a threat."