The centrist party of Albert Rivera, which expanded from a regional Catalan party to a nationwide force early this year, has overtaken both the PSOE and Podemos and would probably be the main kingmaker, according to the Metroscopia poll.
The survey, published on Sunday in El Pais newspaper showed that the ruling PP would win a national election but fall well short of the majority it currently enjoys, capturing just 23.5 percent.
Ciudadanos, meaning Citizens, would come a close second winning 22.5 percent of the vote, a leap from 16.1 percent in early September.
The partyhas been steadily gaining ground winning over Spaniards with its message of moderate change, leaving Podemos, the radical left anti-austerity party of Pablo Iglesias in its wake.
The latest survey showed support for the PSOE had fallen to 21 percent while Podemos would bring in around 17 percent, a drop from its popularity peak of 28 percent in January.
Podemos va descendiendo su caudal de votos del 28% al 17% mientras Ciudadanos, tras las catalanas, supera el 22% pic.twitter.com/xzeyMUmvac— metroscopia (@metroscopia) November 1, 2015
The survey reinforces the dramatic transformation in Spain's political scene which has changed from the traditional two party contest to a four-horse race.
The poll projected the number of seats each party would get in the national parliament and showed that Ciudadanos would be able to team up with either the PP or the socialists to form a government.
The 35-year old Rivera, who famously stripped off in his first campaign poster nine years ago, is seen as the best regarded politican by far, according to the survey.
He was also considered the favourite choice to be the next prime minister.
Los españoles preferirían como próximo Presidente a Albert Rivera antes que Rajoy, Pedro Sánchez o Pablo Iglesias pic.twitter.com/uLWsIG1OEA— metroscopia (@metroscopia) November 1, 2015