The Democratic Study Group, the 250-member organization behind most of the recent procedural reforms in the House, is 20 years old this year and reaching a turning point in life.

The organization, begun by liberal House Democrats frustrated over inability to crack the southern power structure, was enormously successful in spearheading the drive that blunted the seniority system, spread power to subcommittees and younger members, put House votes on record and opened proceedings to the public and the press.

Imitators in the form of such groups as the Black Caucus, Rural Caucus and Republican Study Group have sprung up all over the place.

Yet its very success has brought problems for the DSG.

The "reform" era it was organized to initiate is largely over, and some of the missionary zeal that infected its members is gone.

Its founding fathers, such as Reps. Morris K. Udall (Ariz.), Frank Thompson Jr. (N.J.) and Richard Bolling (Mo.), are now part of the power structure as committee chairmen.They need the DSG less, and are less active in it.

Today's new Democrats are preoccupied with spending and economic issues, and don't identify with liberalism or the DSG with any intensity.

Moreover, in the last few years liberals have split into two factions -- those loyal to Bolling, Majority Leader Jim Wright (Tex.) and Speaker Thomas P. (Tip) O'Neill Jr. (Mass.), and those loyal to Rep. Phillip Burton (Calif.).

Burton is a shrewd political operator whose bids for majority leader against Bolling and Wright and assaults on the power of the speaker have made the leadership suspicious of his every move.

Rightly or wrongly, DSG is perceived as under the influence of the Burton faction. DSG Chairman Abner Mikva (Ill.) spent the last two years reassuring the leaders that DSG was not out to get them. "There's still a little bit of paranoia that we're being masterminded by Phil," Mikva says.

That's why a contest this week for the chairmanship of DSG is considered important.

Those who think that DSG needs to come in out of the cold and work with the leadership or risk becoming a small, ineffective fringe group are supporting Rep. David R. Obey (Wis.).

Those who fear that a loss of independence will mean a loss of identity and the beginning of the end for DSG are supporting Rep. Richard L. Ottinger (N.Y.).

Obey and Ottinger agree there isn't a dime's worth of difference in their liberal voting records.

But Obey, who sits on the Appropriations Committee and wants to be Budget Committee chairman someday, is a friend of the leaders. They turned to him to clean up the ethics code and House administrative practices after scandals that ranged from Wayne Hays mistress-hiring to Korean influence-buying.

Ottinger, on the other hand, is a member of a gadfly group that has challenged the leadership on such important issues as the deregulation of natural gas.

Both Obey and Ottinger insist that they will not impose their priorities on the organization, that they will consult with the membership and executive committee about the directions DSG should take.

Obey talks in broad terms about uniting liberals to "monitor and respond to the stuff put out by the radical right."

He talks of bringing together older members and younger ones to get to know one another, a process he says has been short-changed because of the rapid turnover in the last six years.

Ottinger talks of independence. "There's no question the DSG ought to be independent," he says. Noting that Majority Whip John Brademas (Ind.) is working hard for Obey, he says: "I'm certainly a very independent guy. I think they do look at Obey as being more malleable than I am. I guess that's why the leadership is less enthusiastic about me."

O'Neill has never forgiven him for trying to get a separate vote on gas deregulation in last year's energy bill, Ottinger says, but he thinks the leadership intrusion might backfire.

Obey denies that he would be a tool of the leadership: "The DSG has to butt heads from time to time. If a fight is necessary... I'll fight it."

The majority leader race of 1976 split the liberals. The Bolling and Burton factions have been hostile ever since. Today Burton backs Ottinger and Bolling backs Obey, but that rivalry has -- the candidates insist -- nothing to do with the DSG race.

"I'm not an instrument of Phil," Ottinger said.

"I'm sick and tired of everything that comes up around here being a replay of the last majority leader race. We ought to quit fighting old personality battles and grow up," Obey said. "We ought to quit niggling over a 1 percent difference in philosophy and get together and agree to be a real force."

Mikva believes that the DSG will survive both the race and its identity crisis, which he says "has always been there, even from the time we were first meeting in a telephone booth."

Mikva says DSG has always been an evolutionary force, not a revolutionary one trying to overthrow the leadership. He points out that small changes that seemed not to matter at the time, such as votes to confirm chairmen, loomed larger as time passed. He believes DSG can become active only in those issues on which it can find a broad consensus. He notes, for instance, that DSG had to sit out the Vietnam war because of internal divisions. He also believes that the time for tension with the leadership might be ended, since it generally has gone along with DSG proposals.

As to what DSG will do in the future, it's clear Mikva thinks the cycle will begin again: "After a while all reforms become repressions."