There are all sorts of explanations going around in political circles these days for the low popularity rating of City Council member Douglas E. Moore, who is now running for council chairman in the Sept. 12 Democratic primary. A Washington Post poll released this week showed Moore trailing City Council member Arrington Dixon in the chairman's race by a margin of more than 2 to 1.

The most common explanation for such a dismal showing by Moore, who was once the top vote-getter among the at-large council members, is that the former chairman of the Black United Front has stripped himself of the necessary political advice on how best to handle his potentially abrasive style and is doing a very effective job of defeating himself with his own antics.

Nearly every politician has an alter ego with an outside perspective, a woodshed adviser who calls a lot of the political shots. They are the ones who are not too awed by the candidate to put their foot down at the right moment and say, "Excuse me, sir, but if you do what you're about to do, you'll kick yourself in the rear end."

Robert F. Kennedy did it for his brother John when John was president. Ivanhoe Donaldson handles the chore for Council Member Marion Barry. City Administrator Julian Dugas is said to share that role in Mayor Walter E. Washington's political life with several others, just to cite a few examples.

Phil Watson, the political adviser who managed Moore's 1974 campaign, used to do it for Moore, but has not been a regular in Moore's circle of advisers during most of the years since. "You know who Doug's been talking to?" one of his colleagues on the Council said recently. "I'll tell you who. Doug Moore talks to no one. He talks to himself. He talks to his navel."

Moore is the first one to disagree with this assessment. "I do have a cadre of strong black intellectuals," he said the other day, including a few labor leaders, ministers, political scientists and close aides whom he consults on key decisions.

But others who observe Moore say if that is the case, those advisers are too much of a political looking glass, and are not telling Moore the obvious. "Doug's organizing his whole campaign around his personality," one local political operative said the other day."The problem there is when it comes to personality, he loses every time."

One Moore acquaintance agreed somewhat with that assessment. "When you look at Doug on the issues, no one has challenged him on the issues. They challenge him on personality," the acquaintance said. "The whole poll simply means that the personality aspect of the campaign is what things are riding on."

Moore's loud, sharp and penetrating style has come to the fore during the recent campaign in his sometimes sharp - but colorful and quotable - denunciations of his political opponents, including gay rights advocates, Barry and Dixon. That, this acquaintance feels, may win Moore applause and points with some of those around him who are ideological purists and like to see him on the offensive. But not with the voting public.

"People don't like to witness a fellow being beaten up and Arrington is being portrayed as the clean-cut guy," the acquaintance said. What's more, the acquaintance added, that kind of aggressive posture reinforces the rabble rousing image suggested by all of Moore's well-publicized scrapes with the law.

That is an assessment with which one well-placed source close on Dixon agrees. "When Doug does his jump up and down number, it's to our benefit. People don't want that for a council chairman," the source said.

Moore's approach is just the opposite of that used by former D.C. School Supt. Barbara A. Sizemore, who also ran for public office with a previous reputation as a maverick of sorts, during her nearly successful campaign for City Council last year.

Sizemore seldom raised her voice and hardly ever called names. Instead, she played the part of the perfect lady, often leaving the impression that all of those "horrible things" that had been said about her could not be true about such a mile-mannered woman.

One lesson that some of Moore's closest backers feel is inherent in the Post poll - which showed Moore losing to Dixon 53 percent to 21 percent - is that Moore does have die-hard supporters who will vote for him, and that base can be expanded. What Moore has to do now to bring these people around, they say, is to change his style, so that his actions aren't speaking so loudly that no one hears his words.

But, said one Dixon confidant, "I think it's too late. The impression has already been made. People don't forget that easily, and I doubt that the press is going to let them."

Moore says he is not about to change his campaign game plan, but does believe he could win if personality were not the political cutting edge in the contest. "Nobody's talking about the issues in the campaign," he said. "It is irrational for someone to vote against Douglas Moore when they look at Arrington Dixon's record.

That's fine with the Dixon supporters, a Dixon associate said. All along, the associate said, they have tried to say Moore's record is the major reason he should not be council chairman. "By him changing the way he acts on the street," the associate said, "it is not going to change his record of 3 1/2 years on the council."