Voting will take place on Thursday in a closely watched regional election called by Spain following October’s controversial independence referendum.

The snap election pits parties who want Catalonia to be an independent republic against those who wish it to remain a semi-autonomous part of Spain, the BBC reported.

All indications are that the result will be very close.

The Spanish daily El Pais said on its front page on Wednesday that one million undecided voters could have the last word.

An aggregate of polls published earlier this week by El Pais suggested that the pro-independence Republican Left of Catalonia (ERC) will lead the polls, slightly ahead of Ciudadanos (Cs), which wants unity with Spain.

The pro-independence JxCat party of ousted Catalan President Carles Puigdemont was predicted to come third. That would mean no parliamentary majority in favour of independence and possibly lengthy negotiations to form a government.

Separatists who dominated the Catalan parliament declared independence on October 27 after a controversial referendum deemed unconstitutional by Spain, the BBC reported.

Spanish Prime Minister Mariano Rajoy then sacked the Catalan government, imposed direct rule and called the December 21 election.

Prosecutors accused 13 Catalan separatist politicians of rebellion and sedition, including Puigdemont and four others who fled to Belgium.

Other pro-independence politicians are in Spanish prisons.

As a result, campaigning has led to some unusual scenes, with Puigdemont addressing rallies via a videolink from Brussels.