D.C. Mayor Marion Barry took sides last night in a controversial power struggle among Hispanic community leaders over who will run this summer's Hispanic Festival.

In a written statement issued last night through the Mayor's Office of Latino Affairs, Barry said that the District will recognize an election held in Adams-Morgan Dec. 17 to decide who will run the popular summer festival, which has drawn as many as 150,000 people in past years.

The election was declared null and void by the executive committee of last year's festival. Eduardo Perdomo, head of the committee and president of last year's festival, said the winner of the December election violated a rule against busing in voters.

However, Jose Sueiro, the winner of the election, said he won fairly and that there is no provision in the festival's bylaws that would allow Perdomo or the executive committee to annul the results.

Barry's statement last night changed significantly the face of a new election that will be held from 2 to 5 p.m. today at the Marie Reed Learning Center.

Barry's statement reads, "On Thursday, Dec. 17, 1987, the Latino community of the District of Columbia conducted and participated in elections for the 1988-89 Hispanic-American Festival. The secret-ballot election was conducted according to democratic processes, and the District government recognizes the results of that process. The District government will proceed to work with the duly elected president in order to ensure a well-organized and well-run Hispanic-American Festival."

Perdomo said last night that the organizers and candidates for today's election had been told by a city government official that it would take "back seat" in this controversy and let the community decide who should run the festival.

When told of the mayor's statement last night, Perdomo said, "If the mayor is taking sides with these people, that means he's trying to call the shots on who is the leadership of the Hispanic community. The mayor should let the community decide who the leadership is."

Sueiro couldn't be reached last night for comment. But one of the candidates in today's election who lost to Sueiro in December said the move by the mayor last night seemed to be a maneuver of the Office of Latino Affairs.

"It's the old guard attempting to stay in power," said Arturo Griffits. "The old guard is against the people who want change and who want to be part of the process."

Griffits was referring to the prestige that control over the festival has come to mean. He said the election brings to a head a power struggle between Hispanic leaders who have been in power for 15 to 20 years and a new group of leaders who want more of a say in local issues.

There will be three candidates in today's election: Griffits, Israel Lopez, who also lost to Sueiro in December, and Ivan Gonzalez.