Catalonia's former president Carles Puigdemont and his supporters have held a major rally ahead of next week's snap regional poll.
Puigdemont addressed Friday's campaign event in Barcelona via video from Brussels where he fled following the region's unilateral declaration of independence in late October.
"If we want an independent state, let's vote, and let's vote like an independent state and therefore let's defeat pessimism, defeat the darkness of Article 155 and let's help expel the fear from our streets."
Thursday's crucial vote remains on a knife-edge with polls predicting a hung parliament.
But even if Catalonia's pro-independence movement can make the breakthroughs it needs to win an absolute majority in the regional assembly, some separatists fear Madrid will refuse to loosen its tight grip on the region.
One woman said: "What worries me is that, even if the pro-independence parties get an absolute majority, the state is going to continue to apply the (article) 155 so the situation won't move forward."
Should a hung parliament be the outcome of the December 21 poll, it is likely to add more uncertainty to a political crisis which has rocked Spain to its core.