GOP'S LAST GASP REPUBLICANS PREP HARD FOR KEY ELECTION.(Main)

Byline: Robert Borsellino State editor

By 11 Monday morning, Robert Haggerty had been at work for five hours. He'd cleaned some of the clutter from his still- cluttered desk, returned a few phone calls and put together a schedule for his staff.

Around the room - on tables, desks, chairs, the floor - were the charts, schedules, polls and calendars that are the weapons of the political operative.

A large map of New York's 61 state Senate districts dominated the office.

For Haggerty, a former union official who heads the New York state Senate Republican Campaign Committee, keeping his party's last power base at the Capitol has become less a job than a crusade.

"Just 92 days to go," said the one- time director of operations for the Civil Service Employees Association's political action fund.

While the Democrats have a secure hold on the governor's mansion and the Assembly, the Republicans must fight hard to retain control of the Senate.

After this year's census, a Democratic Senate - in concert with a Democratic Assembly - would redraw the state's district lines so that the Republicans would likely become bit players for the rest of the century.

They now have a 33 to 26 advantage in the Senate, with two vacancies. But one of those vacant districts, the St. Albans area of Queens where incumbent Sen. Andrew Jenkins was convicted of money laundering, is so heavily Democratic that the GOP hasn't …