Three polls for Spanish newspapers El Pais, La Vanguardia and ABC show the main pro-independence movement Junts pel Si (JxSi, or the "Together for Yes" coalition) winning between 63 and 67 seats, or around 41 percent of the vote, Reuters reported, just shy of an absolute parliamentary majority of 68 seats.
Catalonia is an important part of Spain's economic and political life, making it worth fighting for. It is a major contributor to the Spanish economy with nearly 19 percent of Spain's gross domestic product (GDP), according to research by the Organization for Economic Co-operation and Development (OECD).
If it succeeds in becoming independent, not only could Spain lose a substantial financial contribution, it could encourage another region fraught with separatist sentiment – which in the past manifested itself in bombing campaigns -- in the autonomous Basque country to bid for full independence.
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Voter turnout could be decisive for pro-independence parties, according to Antonio Barroso, senior vice president of risk consultancy Teneo Intelligence.
In a note Tuesday, Barroso said that if Mas is re-elected, the pro-independence movement will gain momentum but only if the awkward coalition of pro-independence parties overcome their differences.
"Although Mas' re-election will test the unity of the secessionist movement, pro-independence parties will make symbolic moves towards a Catalan state if they obtain a majority, prolonging the stalemate with the central government," he said.
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He believed that the coalition would tread carefully, adopting "incremental steps" towards independence with the idea being to keep the Catalan political momentum alive without taking it to a breaking point with the Spanish central government."
Strategists at Rabobank appeared more relaxed about the possibility of the separatist coalition succeeding, however, saying in a note Wednesday that the main parties "are from the opposite ends of the political spectrum (the right and left respectively) with their only common ground being a call for independence. Thus the thinking is that they will struggle to govern effectively together."