ANNAPOLIS, AUG. 15 -- The abortion issue appears to be helping some Maryland Senate challengers attain a status they usually can't count on: relatively equal footing in raising campaign cash.

In a half-dozen state Senate races in which abortion is a major issue, challengers in four have raised nearly as much, or more, in campaign funds as the incumbents.

But the issue seems to cut both ways. Antiabortion challenger Larry E. Haines has raised more money than abortion-rights supporter Sen. Sharon W. Hornberger in the Republican primary in Baltimore and Carroll counties. In Montgomery, Del. Mary H. Boergers has raised four times as much money as antiabortion Sen. S. Frank Shore in their Democratic primary.

Since last winter, when the Senate was deadlocked for more than a week over legislation guaranteeing a woman access to abortion, groups on both sides of the issue have been preparing for a fund-raising showdown in the elections. The outcome of the Sept. 11 primaries will strongly influence whether the General Assembly approves abortion legislation next year.

Political action committees formed to support candidates on both sides of the issue have raised nearly $150,000 so far this year.

Some Senate veterans and leaders of political action committees downplay the role of the abortion issue in fund-raising, noting that contributions from such single-issue groups make up a relatively small percentage of overall money collected by the candidates.

"It doesn't generate dollars," said Senate President Thomas V. Mike Miller Jr. (D-Prince George's). "Abortion is an issue with the voters; it's not a matter between candidates and their contributors."

However, a leader of the Maryland chapter of the National Abortion Rights Action League, Karyn Strickler, said the issue goes beyond direct involvement of political action committees.

"I have a strong suspicion that individuals are giving based on this issue, and that some organizations that are not one-issue groups are basing decisions partly on it," Strickler said. "Some of the money may not look like pro-choice money, but it may be partly pro-choice money."

Phil Andrews, executive director of Maryland Common Cause, said it is unusual for challengers to raise nearly as much money as incumbents. In 1986, he said, 80 percent of PAC money went to incumbents. The fund-raising advantage, he said, helps explain why more than 90 percent of Maryland legislators are successful when they run for reelection.

"It's fair to say that the bigger role money plays in races, the better it has been for incumbents," Andrews said.

This year, incumbent senators apparently don't have an automatic advantage in some races.

Boergers reported raising $83,309 in her attempt to oust Shore, who said he has raised $20,900. In neighboring District 18, abortion-rights leader Del. Patricia R. Sher said she raised $38,600 for the Democratic primary, compared with $43,870 for Sen. Margaret C. Schweinhaut, an abortion foe. Schweinhaut's total includes a $10,000 personal loan.

In Prince George's County, Democratic challenger Terezie S. Bohrer reported contributions totaling $31,267, while the District 23 incumbent, Leo Green, said he had raised $34,000. Green was a leader of the Senate filibuster that blocked passage of abortion-rights legislation, and Bohrer has made her support for the legislation a key in the primary campaign.

In District 26 of Prince George's, Sen. Frank J. Komenda, who opposed the legislation, has far exceeded the contributions of his abortion-rights challenger in the Democratic primary, Del. Gloria Gary Lawlah. Komenda said he had raised $72,085 to Lawlah's $31,002.

Andrews said that the overall strength of candidates in abortion-oriented races could affect contributions from unrelated PACs.

John Harrison, treasurer of the Maryland Realtors PAC, said a candidate's stand on abortion is not a factor in whether the group will contribute. However, he conceded, "Sometimes we've been known to give to both candidates, and sometimes we look very carefully at who we think is going to win a race."

Campaign contributions raised in selected Maryland Senate primary races in which abortion is a major issue. Montgomery County

District 17: Sen. S. Frank Shore, $20,900; Del. Mary H. Boergers, $83,309.

District 18: Sen. Margaret C. Schweinhaut, $43,870; Del. Patricia R. Sher, $38,600. Prince George's County

District 23: Sen. Leo Green, $34,000; Del. Terezie S. Bohrer, $31,267.

District 26: Sen. Frank J. Komenda, $72,085; Del. Gloria Gary Lawlah, $31,002.

Source: Maryland State Administrative Board of Election Laws.