The Federal Election Institute, the public body that oversees the voting, has taken the Nulo campaign seriously enough to put forward a counter campaign, and seven of the eight political parties in Mexico City gathered to argue against the Nulo effort. Political analysts say about 2.5 per cent of the ballots cast in any Mexican election are nullified, most unintentionally. With the Nulo campaign seeming to gain support by the day, spoiled ballots next month are expected to be higher—from 5 per cent of the voters to significantly more,.

But there is a great difference of opinion on what effect even strong support for Nulo will have, since under Mexican voting rules, Nulo cannot win.

Detractors of the Nulo campaign counter that those spoiling their ballots are doing damage to democracy and allowing other voters to decide who will govern them. Ravi Singh, an Internet consultant from the United States who is helping several Mexican candidates with their online campaigning, described the Nulo effort to an American reporter as “unpatriotic” and “like a bunch of babies crying”.

Experts do not expect a surge by Nulo to significantly change the distribution of support for the various parties. The PRI has been leading in most polls, followed by the National Action Party and, in a distant third place, the left-leaning Democratic Revolution Party.

Turnout is typically low for Mexico’s midterm elections, which take place every three years, and some polls suggest that as many as 60 per cent of voters will stay home next month, supporting none of the real candidates and not Nulo, either.