The central government insisted Sunday’s poll will not go ahead as police sealed off a swathe of schools which had been designated as polling stations.
But pro-independence leader Carles Puigdemont, President of the Catalan Generalitat, told crowds in Barcelona that Catalonia had already “defeated the state” in its bid for autonomy.
At a rally attended by thousands in the city to mark the end of the campaign on Friday, he boasted: “We have already won.
“We have overcome the fears, the threats, the pressures and the lies. We have defeated a state that didn’t want to let us get here.”
Mr Puigdemont said he was convinced the ballot would take place tomorrow and would finally pave the way for an independent Catalan state.
He declared: “Let’s end the process and start the social, economic, cultural and national progress”.
“We have achieved what was only a dream, on Sunday we have a date with the future.
“Next week we will begin to walk firmly, dressed in sovereignty and the dignity that the State wanted to take away from us.”
Bands played at the closing rally where people constructed the slogan “Referendum is democracy” in big white letters on a stage in front of a cheering crowd, many draped in the red-and-yellow Catalan flag.
The Generalitat’s Vice-President, Oriol Junqueras, said the campaign had been marked by the “firmness and serenity” of people in defending their rights.
He told supporters: “To build a better world for us and for our children, Catalans, don’t give up. We are not afraid.
“Democrats around the world, we are the product of many difficulties and many defeats, but we are also the seed of all victories.”
Police have confiscated thousands of voting slips, and courts have fined and threatened to arrest regional officials.
Catalonia’s High Court ordered Google to delete a smartphone app that the Catalan government was using to spread information about the vote.
Madrid, which claims the authority of a constitution that declares the country to be indivisible, remains opposed to the vote, but also hopes Sunday will be peaceful.
Government spokesman Inigo Mendez de Vigo warned organisers would face criminal charges and said: ”I insist that there will be no referendum on October 1.
In a sign that large crowds are expected on the streets on Sunday, department store chain El Corte Ingles said it would shut three stores in central Barcelona. The government said airspace above the city would also be restricted.
Spain’s government said today that police had sealed off 1,300 of 2,315 schools in Catalonia which had been designated as polling station.
But around 163 schools which have been earmarked as voting centres have been occupied by independence supporters.
People have also camped out overnight in schools in an effort to prevent an order by the head of the Catalan regional police to evacuate and close polling stations by 6am on Sunday, before the voting opens at 9am.