Catalonia's pro and anti-independence parties are supported by almost the same amount of people, a latest opinion poll has shown. If new regional parliamentary elections were held now, it could see pro-unity parties winning, but with an advantage of less than one percent.

Parties opposing Catalonia's independence from Madrid attracted 43.4 percent support in the poll conducted by Sigma Dos for the El Mundo newspaper. Those in favor of the region's secession from Spain were supported by 42.5 percent.

One thousand respondents "throughout the community" were interviewed for the poll organized by the newspaper which generally opposes the independence movement. It reported that the survey was held this week, between 23-26 October, a day before the parliament of Catalonia declared independence.

However small the pro-unity's lead, pro-independence lawmakers could lose their current absolute majority in the 135-seat parliament, according to the findings.

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With at least 68 seats required to secure a majority, the hardline independence party, the Popular Unity Candidacy (CUP) would win seven seats (three down), while two other parties supporting secession, the Catalan European Democratic Party (PDeCat) and the Republican Left of Catalonia (ERC) currently represented in the Junts pel Si alliance with 62 seats, together would win between 54 and 58 seats, the poll showed.

Since the latest Catalan regional elections held in September 2015, the three pro-independence parties have had 72 seats in parliament. The CUP has already announced it would not take part in any new elections set by Madrid. The parties who have expressed support for unity with Spain – the Citizens Party (Cs), the Socialists' Party of Catalonia (PSC) and the People's Party (PP) received 39.1 percent of the votes in 2015.

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Spain's central government this week ordered the snap vote for December 21 to decide a new regional parliament, having dismissed the current government led by Carles Puigdemont. The move came immediately after Catalan lawmakers announced independence Friday, based on what they call a "mandate to secede" following the October 1 referendum. The plebiscite was declared illegal by Madrid. The Puigdemont parliament also claims it still holds power.

Spain has been swept by protests ahead of and after the vote on Catalonia's independence. Hundreds of thousands have since taken to the streets, with both pro and anti-independence protesters consistently rallying across the country.