Beaming at state Republican officials who had come to sing his praises at a carefully orchestrated resurrection rally here today, Maryland Congressman Robert Bauman declared he would win reelection next week despite a poll showing him trailing his opponent by 21 points.

The embattled incumbent, whose political career has been threatened by his own disclosure of alcoholism and "homosexual tendencies," said a poll taken for the Baltimore Sunpapers was "significantly different" from polls taken for his own campaign, one of which showed him 6 points behind challenger Roy Dyson.

"I'm ready to go out there and knock 'em dead in Cecil County," said Bauman of his scheduled Monday campaign stops. "We're going to do very well . . . we're going to win."

The three-term incumbent appeared fiesty and confident at the press conference, which his staff had set up. Republican officials were invited to come and show their support for Bauman, now entering the final week of a campaign for his political survival.

The GOP officials who took them up on the offer included state party chairman Allan Levey, Maryland's Reagan-Bush campaign coordinator Donald Devine, Republican National Committeewoman Louise Gore and a sprinkling of county and legislative officeholders.

Although the press conference was held at the Maryland Inn here, in the heart of her congressional district, Rep. Marjorie Holt, Bauman's ideological comrade in Congress, was absent, pleading a business engagement in Washington. She did, however, send along a telegram, stressing her support for the "whole GOP ticket."

Far more enthusiastic were telegrams from GOP congressional campaign chairman Guy Vander Jagt and liberal Republican Congressman Paul Mccloskey of California, and the words of those who traveled here to show their support.

Levey introduced Bowman "as one of the more courageous men I know for what he has endured and what he promises for the First District." Bauman rose to declare that he had faced his problems and that the momentum now was on his side in the race against State Del. Dyson, a southern Maryland Democrat.

The sun poll and another taken by The Salisbury Times, the largest newspaper in Bauman's congressional district, showed results that contradicted those assessments.

The Sun poll showed Dyson with 51 percent of the vote to Bauman's 30 percent, with about 19 percent of the 400 persons interviewed undecided.

The poll taken by the Times in Wicomico County, one of the larger counties on the Eastern Shore, showed Bauman trailing by nearly 23 points, with about one-third of the voters undecided.

Still another poll, released yesterday by Washington television station WDVM (Channel 9) showed Dyson leading Bauman 43 percent to 28 percent. The station said its latest poll shows Dyson's strength eroding from 51 percent three weeks ago when Bauman's was gauged at 29 percent.