MADRID (Reuters) - Support for Spain's ruling Socialist Party has dropped since an inconclusive election in April, according to a poll of polls published on Tuesday which suggested no party or bloc would win a working majority in parliamentary elections on Nov. 10.
Spain has held three elections in four years but each produced minority or short-lived governments as political leaders struggled to adapt to the new parties that ended years of dominance by the conservative People's Party and Socialists.
The poll of polls published in El Pais newspaper suggests that the latest attempt to end the political stalemate with another election is unlikely to succeed.
It put the Socialists of acting Prime Minister Pedro Sanchez on 27%, down from 28.7% at the April election, while its main rival, the People's Party, would get 21.6% of the votes, up from the 17.1% they received last time round.
Most of the polls included by El Pais were carried out after protests erupted in Catalonia following the Oct. 14 sentencing of nine independence leaders to up to 13 years in prison.
Various recent polls have indicated that support for the Socialists has declined since the sometimes violent protests while parties on the right calling for a stronger stance against separatism have received a boost.
Another poll published on Tuesday was at odds with recent surveys as it showed the Socialists would emerge the clear winner, with the potential to head a left-bloc majority that would not rely on regional separatists.
However, the survey by Spain's state-run Centre for Sociological Studies (CIS) - the largest of its kind in Spain - was carried out before the sentencing of the independence leaders and subsequent unrest in Catalonia.
The CIS poll suggested the Socialists could win between 133 and 150 seats in the 350-seat Congress, while the People's Party would receive anywhere from 74 to 81 seats.
While that would leave the Socialists short of the 176 seats needed for a majority, other left-wing, non-separatist parties, such as Unidas Podemos, would earn between 37 and 45 seats, according to the CIS poll.
(Reporting by Belen Carreno; Writing by Ashifa Kassam; Editing by David Clarke)