Alexandra Jane Dukakis, the first grandchild of Massachusetts Gov. Michael S. Dukakis, was born Wednesday, more than a week overdue. The baby was delivered after a difficult pregnancy that forced her mother, Lisa Dukakis, 33, to remain in bed for months and abandon the presidential campaign that occupied the rest of the family for most of 1988. The new father, John Dukakis, 30, managed the Southern primaries for the campaign.