The conservative People’s Party of Spain is likely to defeat the Socialist Workers’ Party (PSOE) to win the most seats in the lower house of parliament in the upcoming national election, according to a poll conducted by the El Mundo newspaper on Saturday.

According to pollster Sigma Dos, the survey, conducted between June 26 and 30, showed the PP expanding its advantage over Prime Minister Pedro Sanchez’s PSOE.

The poll estimated that the PP would get between 140 and 143 seats in the 350-member lower house, up from 140 in the previous poll held between June 16 and 23. The PSOE would get between 102 and 105 seats, it showed, compared with 102 in the previous survey.

Sumar, the far-left grouping that is combining with current junior coalition partner Podemos to fight the election, would get between 31 and 33 seats, down from 35 seats in the previous poll.

The far-right Vox party, the PP’s likeliest post-election ally, would get 34-36 seats, compared with 35 seats previously.

A likely coalition between Vox and the PP could reach an absolute majority, with the parties on a maximum of 179 seats, more than the 176 needed.

Sanchez called a surprise snap election on May 29 after his party and Podemos were routed in regional and municipal ballots. Sanchez said he would lead the party and seek to remain prime minister.

With the prospect that neither of the two main parties will secure an outright majority, the election is shaping up to be an ideological battle between those opposed to a government that would include Vox and those who oppose the current minority coalition that includes far-left Podemos.