Massachusetts Democrats rallied in support of Rep. Gerry E. Studds (D-Mass.) yesterday and several predicted he could survive politically the disclosure Thursday that he had a homosexual encounter with a House page in 1973, while Illinois politicians were more pessimistic about the fate of Rep. Daniel B. Crane (R-Ill.), who has admitted having a sexual relationship with a 17-year-old female page in 1980.

Studds told reporters Thursday that he will not resign because of the incident, and Crane's press secretary said yesterday that at this point Crane plans to remain in Congress. Crane was home in Illinois yesterday with his wife, Judy, and six children, aged 3 to 12, and Studds was "taking a few days to himself," according to his press secretary.

A vote is scheduled for Tuesday on the House floor on a recommendation by the House Ethics Committee that both be reprimanded, the lightest punishment the panel can request for misconduct by a member.

The ethics committee also alleged that James Howarth, who until last December was in charge of overseeing House pages, engaged in sexual relations with a female page in 1980 and may have bought cocaine in the Capitol. Howarth has challenged the allegations, and that investigation will continue, according to an ethics committee staff aide. Howarth could not be reached for comment yesterday.

The head of the investigation, special counsel Joseph Califano, meanwhile estimated that the year-long investigation into sexual misconduct and drug activity on Capitol Hill so far has cost about $1 million, The Associated Press reported.

"I think he's cooked," said Illinois Republican national committeewoman Crete Harvey, when asked about Crane's political future. "I can't see that his constituents will vote for him," she said, adding that he comes from a conservative district.

"This is a very, very conservative area," said Robert S. Redfern, the Republican chairman in Crane's district. "Something like this would have a drastic effect on anybody . . . . People don't approve of this at all."

"It's a blow to the Republican Party in this part of the state, there's no doubt about that," Redfern added. "The party right now is in shock."

In Studds' district, Democratic party leaders said the congressman will be damaged by the ethics committee report, but several cautiously predicted it would not be politically fatal to him.

"The congressman has a unique degree of support in the congressional district," said Massachusetts Democratic national committeewoman Mardee Xifaras, a former staff aide to Studds. "Most of the people I have talked to today think he will be evaluated on his congressional record . . . . Hopefully, he will serve us for many years to come."

"I don't think it is for me to judge his personal life," said New Bedford Mayor Brian J. Lawler. "He has done a good job representing the area in Congress. To what extent this will hurt him, only time will tell."

Some local Republicans and one of the district's most influential newspapers, The Quincy Patriot-Ledger, called for Studds' resignation, however.

Massachusetts Republican Party Chairman Andrew Natsios issued a statement calling for new elections in Studds' district, saying that "it is not a question of sexual preference, which is his own private business, but the deplorable lack of good judgment shown in getting involved and attempting involvement with individuals who are both minors and employes."

The Patriot-Ledger praised Studds' record but said his effectiveness was "irreparably shattered" by the disclosures.

Studds' homosexuality, which he disclosed publicly for the first time Thursday, apparently was not news to many of his constituents, and most local politicians said they had heard rumors of it before.

After winning his seat narrowly the first time in 1972, Studds ever since has won every election handily in the formerly Republican district, the last time with 70 percent of the vote.

Both supporters and opponents say Studds has built strong ties in his district through constituent service and frequent town meetings.

Gordon Nelson, the Republican national committeeman for Massachusetts, said it is too early to tell what the fallout will be for Studds politically, but that he would expect to see conservative Democrats running against him in the next primary.

Crane won his third term with 52 percent of the vote in 1982, and several Democrats already have indicated that they plan to run against him next year.

His brother, Rep. Philip Crane (R-Ill.), issued a statement expressing compassion for the Crane family and saying the disclosure is a "personal matter between Danny, his wife and children and God Almighty."

The offices of both Crane and Studds reported that the calls to their district and Washington offices were overwhelmingly favorable, with few calls for either man to resign.

Crane's press secretary, William J. Mencarow Jr., also apologized yesterday for a remark he made on Thursday that "there would be no Congress" if all congressmen who slept with young women had to resign. He said yesterday that he regretted the "intemperate" remark and that the investigation had vindicated the House of Representatives.