Remember all those predictions that 1990 was going to be a Republican year in Massachusetts? What seemed the best opportunity in two decades for the GOP to capture the governor's office seems to be evaporating in the wake of a lackadaisical Republican campaign.

The Republican Governors Association (RGA) has not included Massachusetts among the states where the national party has determined its chances of winning a governorship in November are strongest.

William F. Weld, a former U.S. prosecutor, who was trumpeted early this year as one of the GOP's strongest gubernatorial contenders, has only 26 percent support in an August Boston Globe survey, trailing state House Minority Leader Steven D. Pierce by 20 percentage points for the Sept. 18 primary. Neither candidate's standing has changed since a June poll.

Since losing the state GOP's endorsement to Pierce in March, Weld's campaign has floundered. Pierce, meanwhile, has run a cautious campaign, refusing to debate Weld. Other than a few attacks on the Democrats' budget and tax packages, Pierce has been virtually out of the news.

Attention has focused on the heated Democratic race for governor, in which John R. Silber has dominated the debate.

"John Silber has stolen the thunder of the Republicans" by attacking Democratic policies in Massachusetts, said Tom Kiley, a Boston-based Democratic pollster. "He is running a very provocative campaign, he has advanced some conservative proposals."

Silber, on leave as president of Boston University, is in a tight race with former state attorney general Francis X. Bellotti for the Democratic nomination. Lt. Gov. Evelyn F. Murphy is trailing them.

RGA executive director Michele Davis said the Massachusetts race still could get national support, depending on who wins the primaries.

While Kiley said Pierce can still win in the fall, "if Silber is on the ballot in November, it weakens Republican chances even further."