All predictions suggested that the Right-of-centre bloc comprising the PP, Vox and liberal Ciudadanos would fall short of a majority as would the sum of the Socialist party, Podemos and other Left-wing forces.
The two blocs are deeply divided over Catalonia, with Vox, the PP and Ciudadanos all promising a harsh crackdown on the regions pro-independence authorities, while Mr Snchez has called for dialogue to seek common ground.
In the breakaway region, where the build-up to the election has been marked by massive and sometimes violent protests at prison sentences handed down last month to nine independence leaders, Catalan President Quim Torra also made an appeal for a massive turnout.
The will of the people is what decides everything, Mr Torra said as pro-independence parties eyed the possibility of winning more than half of the 48 seats up for grabs in Catalonia.
Ins Arrimadas, Ciudadanos spokeswoman in Congress and an outspoken critic of Catalonias independence movement, was jostled and booed amid cries of fascist as she went to vote in Barcelona.
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