Geraldine Ferraro is sitting in yet another hotel room, pumped full of Tylenol and vitamin C, fighting a cold that's run through the staff and reporters on her campaign trail. It's down time, between planes and rallies, and she's talking and nibbling at the platter of cheese and fruit in a compulsive campaign gesture which -- as she tells everyone -- has added eight pounds to her fighting weight.

Ferraro, candidate for vice president and a working mother, had left Queens at dawn, carrying clothes for her daughter Laura, who's waiting at the next stop. "I bring her a suitcase of clean clothes, then she goes off on another trip and leaves me her dirty clothes," she says with a fond and rueful smile about the things in life that don't change.

This is the beginning of what will be one of her most successful campaign swings through the South and Midwest, but for a moment the frustration that she feels campaigning against the Republican ticket percolates up to the surface. Running a hard-hitting campaign against Ronald Reagan is just a bit like punching Jell-O.

"I have to tell you," she begins. "I talked to my cousin last night. He said, 'You know, we're with you.' Then he said the most amazing thing: 'Everybody I talk to, they say, too bad Gerry isn't running with Ronald Reagan because he's such a wonderful man and she's such a wonderful person.' I said, 'He's not! Don't they look at what he's cost us! Don't they look at where we're coming from on the issues!'

Ferraro is very conscious of the paradoxes of this campaign. She is at the center of one herself. The woman, a political "natural," attracts enormous crowds of the curious as well as the committed. People, especially women, simply want to see her, touch her. But her star quality hasn't yet translated into confidence in her ability. In a Washington Post-ABC News poll comparing her with George Bush as a potential president, the man who can hardly scare up a quorum on the campaign trail beats her 61 to 33 percent.

This doesn't surprise or rattle Ferraro, who attributes it to the wonders of his incumbency, not to her sex. "How many times do people put faith in people they don't know?" she asks. "The polls are reflecting the fact that the man has been vice president of the United States for four years."

It's the second paradox, the one reported by her cousin, that she finds hardest to deal with. "They think he's wrong on the budget deficits, wrong on trade, wrong on arms control," she says, reciting a litany of issues. "But then, when you talk about Ronald Reagan, they say, 'Isn't he wonderful!'anner of a Queens prosecutor who knows she has a perfect case but hasn't yet convinced the jury.

Her conviction, that if the Democrats can only get a handle on the right argument they can win, prompts Ferraro to throw away her speech the next morning at the Chrysler plant in Rockford, Ill., and ask the auto workers there to "Tell me, Tell me" why the polls say one-third of the UAW members will vote for Ronald Reagan. "What is it that would make you vote for him?" she asks the assembly line workers, mostly men, opening a risky, free-wheeling session that transforms their reserved body language and wins their respect.

The same conviction underlies Ferraro's decision to take on a difficult teaching posture in this campaign. This has become, in essence, a show- and-tell election year. Reagan shows himself in a series of photo opportunities and commercials, while the Democrats scramble to tell the other side.

At every stop, Ferraro emphasized the disparity between Reagan's image and his acts. In Nashville, at a speech attacking Reagan's strongest point, leadership, she told the president, "Do not pretend to be a friend of the very things you undermine."

The only hope, as the Mondale-Ferraro people see it, is to hold Ronald Reagan still -- to stop the flags from waving and the music from swelling -- long enough to make him accountable. It's a hope that rests heavily on the debates.

You don't have to be clairvoyant to see Ferraro itching to get Ronald Reagan on the witness stand and cross-examine him. What she will get is a debate with his second and surrogate. For 90 minutes, she will be compared to George Bush, not in abstract notions of leadership but in performance. For 90 minutes, she'll have her chance to turn the show-and-tell campaign into a confrontation.