Rep. Patricia Schroeder (D-Colo.), reporting on a summer of travel sounding out the possibilities of a run for the 1988 Democratic presidential nomination, said yesterday that "in all honesty" she hasn't made a decision but that she will announce it Monday after a weekend conferring with her closest advisers "to see if all this comes together."

Speaking at a National Press Club luncheon, Schroeder said she is confident that she could meet her fund-raising goals but that a major consideration would be whether "we can get enough people who have worked for me before."

She canceled plans to participate in a debate last night in Davenport, Iowa, with the six actively campaigning Democratic candidates.

Asked what the odds are that she will run, she said she isn't close enough to a decision to cite them and that after traveling 75,000 miles to 20 states since June she needs "to look at a lot of factors in peace and quiet and not under the bright lights with a lot of people looking at me."

"There is no reason to get in unless you win," she said. "I have a wonderful platform in the House as senior woman in my party. I can talk about issues. I'm not looking for a platform to speak from."

She described the American people as being ready for a "rendezvous with reality" after seven years of "happy talk" by the Reagan administration.

"I'm not Tinker Bell . . . . The only way I could possibly win this year is . . . if the country is in a shift mood as it was in the 1960s" when John F. Kennedy became the first Roman Catholic president, she said.

Schroeder earlier had said that she would need to raise $2 million. Yesterday, she estimated that she has raised about $1 million after more than 700 fund-raising house parties last weekend and that a test mailing that was "very, very successful" indicated that she could "raise a lot of money, and it doesn't seem to be a problem."

Political observers contend, however, that with such a relatively late entrance into the race she could have trouble assembling an organization. And she has conceded that she would be at a disadvantage in the crucial early states of Iowa and New Hampshire.

Schroeder contends, however, that her campaign would attract issues-oriented activists who would support her over the long haul despite early setbacks.

"The issue is whether America is ready to accept me as a qualified presidential candidate who is a woman," she said. "If my name were Patrick and you look at the qualifications they are certainly equal or better. Fifteen years on Armed Services, arms-control whip, deputy whip for the Democrats."

Schroeder was elected to the House in 1972 and on the House Armed Services Committee has made a reputation as being an irreverent critic of the Pentagon and its Capitol Hill supporters.