Dozens of members of Tunisia’s largest opposition party were arrested this week ahead of the formal start of campaign season for the country’s presidential election, attorneys and officials from the party said Friday. Ennahda, the moderate Islamist party that rose to power in the aftermath of the country’s 2011 revolution, said on Friday that tallies collected by its local branches suggested at least 80 men and women from the party had been apprehended as part of a countrywide sweep that ensnared members from 10 regions. In a statement, Ennahda called the arrests “an unprecedented campaign of …