ELECTIONS : Protesters Take Aim at Mexican Roster : Ruling party’s congressional candidates have little popular support. Some worry disgruntled activists will defect in the August vote.

Bracing for a long throw, the young man in the print shirt drew his arm back and let fly an egg. The crowd behind him cheered as yolk splattered across the district offices of the Institutional Revolutionary Party that has ruled Mexico for 65 years.

No party faithful rushed out to stop the vandalism; the egg-thrower and his cheering section are party faithful. They were sullying their own headquarters to protest the selection of labor boss Carlos Aceves as candidate for federal deputy in their district. They supported a different local leader.

Across Mexico, grass-roots activists have blocked streets and roads, occupied party offices and resigned from the PRI, as the governing party is known, in protest over the congressional candidate roster for the Aug. 21 federal elections.

Officially, party leaders pass off the protests as signs of healthy competition. But privately, some PRI members worry that disappointed rank-and-file activists may stay away from the polls in protest or even vote for the opposition.

“Face it,” one longtime party member said. “They picked some really bad candidates this time.” In too many districts, he said, candidates have influence inside the PRI because of their ties to labor unions, farm groups and party leaders, but they have little popular recognition, much less support. Getting them elected will be tough.

Beyond the quality of the candidates, the protests reflect conflicts over the selection process and the PRI’s identity as a party. Traditionally, the PRI is made up of three groups: labor unions, peasant farmers and a nebulous “popular sector.” The party also has a parallel regional structure of municipal- and state-level activists.

Candidate selection is a power struggle among those groups. The popular sector and regional groups press for a more openly democratic selection process that favors local leaders who will represent each district’s interests.

Unions and farmers press for their quotas of congressional seats to look after their interests. Those seats are usually assigned by the party leadership, often ignoring the wishes of grass-roots activists.

This month, dozens of those activists refused to be ignored. Breaking party discipline, those “natural leaders,” as they called themselves, registered their candidacies at party headquarters, even though they had not received the nod from higher-ups. That forced a vote at their local conventions instead of the usual selection by unanimous acclaim.

Getting union and farm candidates approved by local convention delegates in the face of competition required fancy footwork in some cases. A lexicon of dirty tricks that has grown up around election fraud came into play.

There is “the crazy mouse,” changing the location of a convention at the last minute without advising delegates; madruguete , changing the time; and acarreo , bringing in outsiders to vote as delegates.

Mexican newspapers published accusations of--and in some cases documented--the use of each of those tricks during local party conventions this month.

Some grass-roots activists tried preemptive strikes, such as taking over party offices. After the egg-throwing did not persuade party leaders that they were serious, members of the Independent Popular Organization invaded district headquarters to prevent the local convention.

As pressure grew, some labor candidates stepped down in favor of local candidates.

Party leaders tried to calm protests by offering disappointed candidates congressional seats as party representatives--offices that are distributed after the election based on the percentage of votes each party receives.

But for many, consolation prizes were not enough.

Emilio Serrano, president of the Neighbors Committee of Iztacalco, a Mexico City borough, resigned from the PRI after losing the party nomination for city assemblyman.

“Other parties have offered me a candidacy, particularly the PRD,” he explained, referring to the Democratic Revolutionary Party, whose leadership includes former PRI activists.

Serrano may be disappointed with that party as well.

“None of us can be completely happy with the way our candidates were chosen,” PRD Chairman Porfirio Munoz Ledo acknowledged at a swearing-in ceremony for those candidates. He proposed “re-founding” the party to better ensure respect for democratic ideals.