Pedro Sanchez may have reversed the right-wing tide less than two weeks before the snap general election, according to a new poll.

The CIS (Centre for Sociological Research) survey, which is commissioned by the government, puts the ruling PSOE on 33.3% of the vote.

Such a result would garner between 134 and 143 seats, giving the Socialists a 7.8-point lead over the Partido Popular (PP).

Alberto Nuñez Feijoo’s party is projected to take 25.5% and between 98 and 106 seats. Vox would finish third with 18.4% and between 57 and 65 MPs.

Together, the PP and Vox would hold between 155 and 171 seats, below the 176 needed for an outright majority in Congress.

Frente Amplio is forecast to win 4.7% of the vote and between seven and 11 seats. Podemos could lose its parliamentary representation, with the poll projecting between zero and one seat.

The figures leave open a route for Sanchez to remain in office with support from smaller left-wing and regional parties.

At the upper end of their projected seat ranges, those parties and the PSOE would exceed the majority threshold.

Despite leading the poll, the Socialists have slipped 0.7% compared with the CIS’s October barometer. The PP has gained 3.3 points and Vox 1.3, while Frente Amplio has fallen 1.4 points.

The result differs sharply from the recent 40dB. survey for Cadena SER and El Pais, which put the PP ahead of the PSOE by two points and projected 192 seats for a PP-Vox alliance.

The CIS study draws on 45,074 interviews across 4,190 municipalities, conducted between October 7 and 30. It reports a margin of error of plus or minus 0.5 percentage points for the overall sample.

Its fieldwork covered the announcement of the election and the Urda train disaster, although interviews ended before November’s campaigning.

Voters head to the polls on November 29.