It was a routine bill and the request from the floor of the House of Delegates was routine: One of the members wanted to know if voting on the legislation could be delayed until an opinion on its legality could be obtained from the attorney general.

"How long do you want it delayed?" asked Speaker Benjamin L. Cardin. "You better set a specific time because you never know how long it's going to take to get an attorney general's opinion."

Suddenly, from the press section on the floor, came hissing. Cardin burst into a grin. Later, laughing, he maintained that his had been a "Freudian comment."

The reason for the hissing and for Cardin's sheepishness is the gubernatorial campaign being waged between Cardin and Maryland's attorney general, Stephen H. Sachs.

It will be three years before voters will be paying much attention to a statewide gubernatorial contest, but already Sachs and Cardin are hard at work trying to make the other blink.

Sachs spent the fall campaign running around the state as if his reelection as attorney general were somehow in doubt, although he was to end up with 74 percent of the vote. Still, he was everywhere, stumping hard for the statewide Democratic ticket, showing up at every fund-raiser, political club gathering and ribbon-cutting.

Cardin, without benefit of a campaign for statewide office, was, true to his style, much more low-key during the fall. But since Election Day he has been making more and more speaking appearances and has been quietly meeting with potential big-money contributors, hoping to build up a large bank account for an early media blitz when the time comes.

There are reasons for all this seemingly premature campaigning. The crux of it is the political style of the two men.

Sachs has a reputation among politicians for keeping himself in the public eye; he is also extremely methodical. His first campaign for attorney general was put together so early and so efficiently that, even as someone who had never before run for public office, he had all but ended the campaign by the July filing deadline. He is hoping the same thing will happen this time around.

Cardin is equally methodical. As speaker, his power has been largely based on his ability to get arms twisted without anyone noticing they are being twisted. His gubernatorial campaign is expected to be conducted the same way.

Additionally, both Sachs and Cardin are hoping to make the other one blink early. The two have almost identical constituencies:

Both are Jewish, liberal and from Baltimore, living within several blocks of one another. Sachs, 49, likes to point out that he is 10 years older than Cardin and that, perhaps, Cardin should be a little bit patient. But Cardin will have served five terms in the legislature, two as speaker, by 1986, and there will be little left for him to do there. Already this year, he has shown signs of restlessness in his job.

If Sachs and Cardin stay in the race until the finish, a third candidate could sneak past both of them. Lt. Gov. J. Joseph Curran Jr., if he chose to run, would come to the race with few visible negatives. Mayor William Donald Schaefer is as well-known as any man in the state, although most observers don't think Schaefer will expose himself to a statewide race.

What's more, there simply seems to be something in Maryland's water that makes it impossible for those on the political scene to go more than 48 hours without a political race to talk about.

National politicians often say that only in Massachusetts and Maryland does wholesale talk about the next election begin before the ongoing one is over. In fact, a Baltimore political columnist even devoted a recent column to the question of the 1986 attorney general's race.

Finally, there are the two men's personalities. Neither likes to play the political game of saying, "four years is a long time." Both candidly admit they would like to be governor and can't resist joining in the jibing and kidding of a friendly rivalry.

When this newspaper ran a picture a few days ago of Cardin, taken when he was in need of a haircut, Sachs, looking at the picture, commented, "Could you run that one a few more times?"

Last month when Sachs' daughter, Elizabeth, spent a week working as a page in the House of Delegates, someone asked Cardin, "Which one is Sachs' daughter?"

"The one taking notes," Cardin deadpanned, never missing a beat.

The campaign is heating up. Only 1,265 days left until the Democratic primary.