The latest opinion polls in Spain indicate that the center-right opposition Popular Party could emerge as the largest parliamentary force in Sunday's general election, heralding the first change of government in five years.

Prime Minister Pedro Sanchez called the election after his center-left ruling Socialist Workers' Party lost big in local elections in May. All 350 lower house seats are up for grabs.

Sanchez said during the campaigning that his administration has supported an economic rebound and stifled inflation. Opposition parties called Sanchez unfit to be the national leader because of his conciliatory stance toward a regional independence movement.

Analysts say the Popular Party will likely become the biggest winner in the election but fall short of a majority of the lower house on its own. They say the situation could prompt the party to form a coalition with the far-right Vox party if it hopes to launch a government.

Vox became the third largest parliamentary force in the previous general election four years ago. The anti-immigrant party's current election platform includes opposing efforts to increase gender equality and LGBTQ rights. It is also pushing for Spain to withdraw from the 2015 Paris Agreement on climate change.

The question is whether the Popular Party will form a coalition with Vox if it comes out on top in the election. If that happens, Vox would become the first far-right party to join Spain's government since Francisco Franco's dictatorship ended in the 1970s.