It was a hazy and cold December morning in Madrid, and the central Puerta del Sol square, the neural center of the Spanish capital, stood empty of tourists even though it was already past 10 a.m. "Care to vote, sir?" asked one of the men surrounding a table beneath the equestrian statue of 18th century King Charles III. "What for?" the passerby inquired. "For the republic!" replied the man, raising his voice to a shout.

On December 2, over 23,000 people in 12 districts and four municipalities of the Madrid region voted in an unofficial referendum on Spain's form of government. The result was overwhelming in its rejection of the monarchy: 93 percent of those who cast ballots would prefer to have a president of the republic as Spain's head of state.

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"Almost 1,500 people who support the monarchical regime have determined that it should nonetheless be submitted to the people's will," said the non-partisan grassroots coordinating body behind the Assemblies for a People's Poll on Monarchy or Republic in a press release afterwards.

The vote on the streets of Madrid is one of a many recently. Days before, over 7,300 students took part in a similar unofficial referendum at the Autonomous University of Madrid (UAM). There too the result was a massive victory for the republic, with over 83 percent supporting the end of the monarchy. The UAM vote was the first of a string of ballots to be held in December in dozens of universities all over the country.

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"It's already been 40 years with this constitution, including a monarchy we were never consulted about," said Lucia Nistal, one of the organizers at UAM. "The youth should have a right to decide our future. Not even our parents were old enough to vote for the constitution," she added.

Supporters of a republic argue that Spanish voters did not have a genuine choice when they approved the constitution in 1978

The notion that younger Spaniards are less inclined to support a monarchy is widely accepted as a fact by commentators, though there's no official data. The state pollster, the Center for Sociological Research (CIS), has not asked about the monarchy since April 2015, when the crown was evaluated poorly by respondents.

Alberto Penades, professor of political science at the University of Salamanca and former CIS employee, thinks the reason is that the center doesn't really want to know the answer: "I guess whoever was in charge of CIS at the time didn't want to give easy headlines to the media. I don't justify it, but I think it's obvious, and not something new."

Political row born in Catalonia

The current crisis of the monarchy, be it perceived or real, took a significant turn on October 1, 2017. The attempted secession referendum in Catalonia was seen by most of the major Spanish parties as a direct attack on the constitutional order. Two days later, the king, Felipe VI, appeared on TV to support Spain's unity, backing the government's decision to suppress the vote. Many in Catalonia — and elsewhere in Spain — felt the monarch was taking sides, betraying a tradition of political neutrality.

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Just over a year later the Catalan parliament approved a declaration to condemn the king's speech, urging abolition of the monarchy. The declaration has no legal consequences, but even so, the central government under Prime Minister Pedro Sanchez has asked the Constitutional Court to nullify it, a move that would be unprecedented. Since then, similar initiatives to condemn the king have been put forward in city halls all over the country, and some have been approved.

Many Spaniards were put off by the king's speech after the Catalan government pushed for independence

The main opposition party, the conservative and monarchist People's Party (PP), supported Sanchez's move. "We think it's a direct attack on the crown, and thus, on the constitution," said Paco Martinez, a member of parliament for the PP. Martinez defended the figure of the king as "a symbol of the unity of all the Spaniards."

"If you don't like the constitution, you're free to try changing it, but not breaching it," he said.

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He welcomed the public debate prompted by the unofficial ballots — as long as they were not supported by state institutions, including city halls.

Not everyone in his party feels the same though. In the municipality of Alcobendas, where the conservatives run the local government, voting stations were banned and could only be erected outside of city limits, in a neighboring town.

Referendum called for long ago

"Care to vote, sir?" asked Lucia, one of the voting officers at the Legazpi ballot. The tall man she addressed said "no" and continued on his way. The man, who didn't want to be named, said he would, however, vote in an official poll: "I wouldn't have any trouble taking part if the state organized it, but I don't want to vote if I don't know who's behind it."

Paving the way for an official referendum is precisely one the goals of the vote's coordinators. "This is just a symbolic action, with which we want to bring attention to a debate that we must have," said Luis Gimeno, one of the coordinators of the referendum.

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Spain's constitution, which was approved 40 years ago, on December 6, 1978, defines the state as a "parliamentary monarchy." The dictator Francisco Franco had died three years before, and Spain was beginning its journey towards a democratic society. The constitution was submitted to a referendum and approved by an overwhelming 87 percent of voters.

Beyond saber-rattling

"We already voted in 1978!" a passerby shouted from a distance to the voting officials at the Jacinto Benavente Square polling station.

Ernesto Sarabia, one of those in charge of the ballot box in Legazpi, insisted that argument was not entirely valid. He said voters 40 years ago did not have a genuine choice as to what form of government Spain would have, but rather it was a question of whether the country would remain a dictatorship or not. The king was already part of the deal, and the threat of the military cast a heavy shadow over the vote.

Madrilenos debated whether Spain should be a monarchy or a republic on a dreary winter's Sunday

"Even if the Spanish people vote for a monarchy, we would still have to choose who was to be the monarch. Franco appointed Juan Carlos I [the father of the current king] to succeed him in 1969. We can't allow a dictator to appoint his heir," concludes Sarabia.

Adolfo Suarez, the first prime minister to hold office in post-Francoist Spain, acknowledged in a 1995 interview that he had blocked an official poll on the form of government because he knew a republic would win.

"In 1976, most foreign leaders were asking me to hold a referendum to choose between monarchy or republic, but our surveys showed that we would lose [...] so I included the words 'king' and 'monarchy' in the Political Reform Law of 1977 [which set the scene for the Spanish transition], and that way, I could say it had already been voted on," said the former leader, as he covered his microphone with his hand.

The interview went unpublished until 2016; the referendum was never held.