For most Maryland legislators, last week's special session of the General Assembly was little more than a good excuse to take a day off from campaigning and come here and see old friends.

But for Senate President James Clark Jr. (D-Howard) and Sen. Melvin A. Steinberg (D-Baltimore County), the day was a tense prelude to a major battle the two men expect to wage in December.

The reason: Steinberg wants Clark's job.

Clark has been the Senate president for the last four years. At 63, he is the epitome of the gentleman legislator, a drawling, gravelly voiced farmer with a droll wit and bushy eyebrows that are reminiscent of the raised eyebrows made famous by former U.S. Sen. Sam Ervin during the Watergate hearings.

There are perhaps no two people in the state Senate more different than Clark and Steinberg. Clark is a farmer (he headed out to pick white corn when the session ended Friday); Steinberg, chairman of the Senate Finance Committee for the last four years, is an aggressive, wise-cracking labor lawyer. He is as intense as Clark is relaxed.

For the last month, Steinberg has been lobbying for the votes he will need to unseat Clark. "I'm in very good shape," he said Friday. "In fact, I would say the question now is not whether I can get the votes but whether the votes I have will be chipped away from me."

Reportedly, Steinberg even considered challenging Clark for the gavel during the one-day session. Clark called Steinberg to ask him if he planned a challenge, and Steinberg told him he did not.

"I could have done it, though," Steinberg said.

Pitched battles are the rule, not the exception, in the Senate. It is a brawling, often raucous body, quite the opposite of the House of Delegates, where, as Del. Gerard F. Devlin (D-Prince George's) once put it, "If you debate an issue, people start to think you are a bore."

Not so in the Senate. It is not unusual for the senators to debate the question of whether to debate. Now though, they have a substantive issue, a choice to be made between an incumbent and a challenger with distinctly different styles.

If Clark goes down, and many senators still think Steinberg's fight is an uphill one, it will not be without a struggle. Clark, a fighter pilot in World War II, is not a man to give up easily.

In 1974, he sought the Senate presidency and lost to then-state senator, now U.S. Rep. Steny H. Hoyer. Four years later, he and another Prince George's candidate, Sen. Edward T. Conroy, both sought the presidency. This time, Clark won.

Clark's style as Senate president often has been criticized. Some senators, including Steinberg, insist Clark has let Benjamin L. Cardin, the speaker of the House of Delegates, run roughshod over him, thus weakening the Senate. Gov. Harry Hughes' staffers have been less-than-pleased with Clark's abilities as a vote counter, and Clark angered almost the entire Senate last winter when he insisted on carrying a redistricting fight with the Prince George's delegation to a protracted, bitter conclusion.

Many senators insist it was that fight that may cost Clark his presidency. Privately, Sen. Thomas V. Mike Miller, the leader of the Prince George's delegation, has promised to deliver seven votes to Steinberg, eight if Del. Kay G. Bienen is elected to the new seat in the split Prince George's-Howard district.

Miller himself considered challenging Clark for the presidency but decided to back off and let Steinberg run following a May meeting with Steinberg. He even guided Steinberg to Prince George's political powerbroker Peter F. O'Malley for advice on how to gather votes.

Publicly, Miller says his delegation will remain uncommitted until after the primary. But the entire Senate knows Miller and Clark split forever in the redistricting squabble.

If Steinberg is to win the election in the Democratic caucus in December, he must get the votes of the Montgomery County delegation. For that reason, he spent a long time Friday in heated conversation with outgoing Sen. Victor L. Crawford (D-Montgomery). Crawford will be his point man in Montgomery. "Someone's got to be the wheeler and dealer in this thing," Crawford said with a broad grin.

Vote counting now, when there may be as many as 10 to 12 freshmen senators, is difficult. (Newly elected senators will be eligible to vote in the caucus, although they will not take their seats until January.) Both Steinberg and Clark have been talking to people who seem likely to wind up in the Senate, but if the vote were held today among the 40 Democrats, it would be a tossup.

Which is where the Republicans come in.

Currently, there are seven in the Senate and there may be eight or nine next session. In any case, Senate minority leader Edward J. Mason (who faces a tough reelection fight) has told Clark that if the race is close in the caucus, he will deliver the Republicans to Clark.

Only once in Senate history has the minority party played a role in choosing the president, and both Clark and Steinberg said they don't expect it to come to that. But Clark conceded it could happen, knowing that if it did, the Republicans probably would make him a winner.

"I was hoping it wouldn't come to this," Clark said, sitting in his office Friday afternoon. "But I've been through a few of these in my life, and I'm prepared for another one. I guess you always have to have a contest.

"But it's so early. We don't even know who all the players are yet. But since Steinberg is out there working early I reckon I've got to take some countermeasures."

Steinberg has been telling senators he has a definite plan to change the Senate. "We've got to restructure the Senate," he said. "The majority leader must be a committee chairman so that he or she will be in a position to lead. We need to change the committee structure so that all the power isn't concentrated in one or two committees. We've sterilized some of our committees.

"Also, the decorum of the Senate has dramatically deteriorated. We need someone strong handling the gavel. It's gotten out of hand. We also need a distinct set of rules from the House. The two are equal, but they're also different. There are 141 delegates and 47 senators; you can't handle things exactly the same.

"Ben Cardin has filled a void as a leader with the job he has done as speaker, but we've gotten to the point where the Senate spends all its time me too-ing. That has to stop. We need a voice interjecting the Senate's voice on crucial issues."

Steinberg believes he can be that voice. Clark believes he has been that voice. Apparently neither man intends to back down.

"Before this is over," Miller said, "it could get ugly."

But as Clark said, it's all part of the process, especially where the Senate of Maryland is involved.