MADRID Two weeks ahead of Spain's election, the conservative People's Party (PP) opened up its lead over the ruling Socialist Workers' Party (PSOE) but would still need the help of the far-right Vox party to govern, according to an opinion poll published by a newspaper on Sunday.

A poll carried out by Ipsos for La Vanguardia newspaper between July 3 and July 6 interviewed 2,000 people and showed the opposition PP with 35% of the votes and the PSOE on 28%.

The far-left Sumar party would win 13%, just ahead of Vox with 12.6%, the poll found ahead of the election on July 23.

Voting forecasts would give the PP between 138 and 147 seats in the 350-member lower house, with the PSOE winning between 102 and 112 seats.

Vox - the PP's most likely coalition ally - would win between 32 and 39 seats. Sumar was forecast to win between 31 and 39 seats.

If the results of the poll are correct, it means that a right-wing coalition of the PP and Vox would together win up to 180 seats, enough for an absolute majority.

Alternatively, the PP and Vox together could win up to 170 seats which would give them more than a left-wing alliance of the PSOE and Sumar which the poll forecast would win no more than 150 seats.

The national election was called by Socialist Prime Minister Pedro Sanchez after a disastrous showing in regional elections in May.

All polls have so far predicted that the PP would win the most votes in the elections.

(Reporting by Graham Keeley;Editing by Elaine Hardcastle)