Mexican Leftists Seek Accord on Candidate

MEXICO CITY — Twelve leftist political parties have formed an alliance that will search for a single candidate agreeable to all to challenge the ruling Institutional Revolutionary Party in the 1988 presidential election.

A document made public this week, the result of negotiations that began in November, calls for all 12 organizations to support joint candidates in local and national elections. Similar efforts at unity in the past have failed, usually because of ideological differences or personality clashes among the leaders.