BOSTON--With a tight finish expected, Boston's eight mayoral candidates have planned get-out-the-vote drives for today's nonpartisan preliminary election.

Opinion polls show a two-tier race with four candidates in a virtual dead heat. They are: acting Mayor Thomas Menino; Suffolk County Sheriff Robert Rufo; state Rep. James Brett, D-Boston; and city Councilor Rosaria Salerno.

They are followed by Councilor Bruce Bolling, television journalist Christopher Lydon, former Police Commissioner Francis Roache and Republican attorney Diane Moriarty.

The mayor of Boston can affect Harvard's Business School, the Medical School, and the School of Public Health, all of which are located in the city.

At least three of the candidates have Harvard ties. Brett received an MPA degree from the John F. Kennedy School of Government in 1989. Christopher Lydon's daughter Amanda C. Lydon '94 lives in Dunster House, and the candidate has received considerable financial support from Cambridge residents. Salerno has recently galvanized a corps of undergraduate volunteers for her campaign.

Roache has pledged to push universities to make larger contributions to the city in lieu of taxes.

Anjalee C. Davis '95, the Harvard campus coordinator for the Salerno campaign, said about 25 undergraduates have volunteered over the last few days, contributing to an effort to elect the city's first woman mayor. Students will work at phone banks tommorrow and attend the "big party" tomorrow night, she said.

"There's a lot of enthusiasm, a lot of momentum," Davis said.

The candidates made a last-minute pitch for the undecided vote last night, giving five-minute speeches at the traditional pre-election rally in the city's Dorchester neighborhood.

Even as he listened to the candidates, 22-year-old Graham Morrison said he still hadn't made up his mind.

"I won't know 'til I walk in," said Morrison, who considers himself well-informed. At his job as a Suffolk Superior Court clerk, "We talk politics all day."

Morrison's reaction to their speeches: "I thought they all sounded stupid."

The scene for the rally was out-doors at the Adams Corner, where the neighborhood's pubs, hardware store, deli and convenience store were swathed in red, white and blue bunting.

Many in the crowd of 1,500 held political signs for mayoral and city council candidates, making the corner look like a national convention.

Hoisting his sign for council candidate Richard Ianella above the others, Tim Teehan said, "The competi- tion here is unbelievable."

Theatrics abounded. A wave of Brett supporterswalked down a hilly street by candlelight. FourRufo supporters, each wearing a letter of his namelit up his name in white lights, on their redsweatshirts.

A man in a baseball cap walked around with atray of baked goods. "Scones," he said, "forMenino," and looking embarrassed, he melted intothe crowd.

Finally, Elvis appeared on a rooftop, bearing aBrett sign.

The crowd reveled in the crisp evening air, butthe weather was predicted to turn rainy and nottop 62 degrees on election day.

"Bad weather is predicted which will keep folksat home unless a candidate's organization pullsthem out," said George Bachrach, a former statesenator and political analyst. "The person bestequipped to do that can pull off an upset."

State and local officials were predicting ahigh turnout despite the weather forecast, due tovoter interest in the contest for the seat lastheld by Raymond Flynn, now U.S. Ambassador to theVatican.

"I just anticipate that all those politicalorganizations for those candidates will turn out agood number of voters," said John Donovan Sr., thecity's chief registrar of voters.

Donovan predicted that 49 to 52 percent of thecity's 225,196 registered voters would go to thepolls in the election, which will narrow the racefor mayor to two candidates.

Menino has the coveted spot at the top of theelection ballot, with Rufo listed last.

Ira E. Stoll contributed the reporting ofthis story.