The rally was organised by the Sardines movement, which was launched last November to fight the far right, particularly the anti-immigrant politician Matteo Salvini, a leading member of Italy’s previous coalition government.
Salvini’s resurgent League party and his rightist allies are looking to end almost 75 years of unbroken leftist rule in the wealthy Emilia-Romagna region in Sunday’s elections, with latest polls putting the two camps neck-and-neck.
A victory for Salvini could lead to the collapse of the government formed by the leftist Democratic Party (PD) and the anti-establishment Five Star Movement (M5S).
This in turn could lead to national legislative elections, which Salvini is pushing for.
“This [regional election] will probably be a turning point for Italian politics,” Mattia Santori, one of the founders of the Sardines, told the Italian daily La Repubblica.
“We have shown that we can do politics without low blows.
“We have already defeated populism.
“Salvini goes to the bars and does selfies ... We fill up the squares.”
Last October, the League won a historic victory in elections in the central Italian region of Umbria, a left-wing bastion for half a century.
Salvini has been campaigning across Emilia-Romagna for weeks, visiting more than 100 municipalities in an attempt to secure a shock victory.
Organisers said the Sardines protest on Sunday had drawn between 35,000 and 40,000 people, while police did not immediately provide their own crowd estimate.
