Portugal’s ruling centre-right Democratic Alliance (AD) is poised to win the most votes in an early parliamentary election, but is short of a full majority, exit polls have shown, paving the way for more political instability in the country.

Sunday’s election, the third in as many years, was called just one year into the minority government’s term after Prime Minister Luis Montenegro failed to win a parliamentary vote of confidence in March when the opposition questioned his integrity over the dealings of his family’s consultancy firm.

Montenegro has denied any wrongdoing, and most opinion polls showed that voters have dismissed the opposition’s criticism.

The election, also dominated by issues such as housing and immigration, follows a decade of fragile governments. And the only one of those governments to have a parliamentary majority collapsed halfway through its term last year.

Exit polls published by the three main television channels – SIC, RTP and TVI – put Montenegro’s AD as receiving between 29 percent and 35.1 percent of the vote, garnering the biggest share but again no parliamentary majority, similar to what happened in the previous election in March 2024.

Outside the polling station where Montenegro voted in the northern city of Espinho, Irene Medeiros, 77, told Reuters the “best candidate must win”, but that she feared more uncertainty ahead.

According to the exit polls, Montenegro’s main rival, the centre-left Socialist Party (PS), garnered between 19.4 percent and 26 percent of the vote, nearly tied with the far-right Chega party’s 19.5 percent to 25.5 percent share, which is higher than the 18 percent it won in 2024. Montenegro has refused to make any deals with Chega.

With that tally, the DA could get between 85 and 96 seats, short of the 116 needed for a majority in Portugal’s 230-seat parliament. It could form a minority government or forge partnerships with smaller parties to obtain a majority.

Most official results are expected by midnight (23:00 GMT).

For the last half century, two parties have dominated politics in Portugal, with the Social Democrats, who head the DA, and the PS alternating in power.

Public frustration with their record in government has fuelled the search and for growth of new alternatives in recent years.

“This campaign was very, very weak, had ridiculous moments, like clownish. Very little was spoken about Portugal within the European Union – it’s like we are not part of it,” teacher Isabel Monteiro, 63, told the Associated Press news agency in Lisbon, adding that she felt “disenchantment” with all parties.

Political scientist Antonio Costa Pinto said the new parliament would likely be similar to the last, and it was impossible to predict how long the government would last, as it depended on factors ranging from the international situation to the AD’s ability to reach deals with other parties.

“The only doubt is whether the AD will form a new minority government … or whether it will form a post-electoral coalition with IL, even if this coalition does not guarantee an absolute majority,”, referring to the pro-business Liberal Initiative (IL) party, according to Reuters.

Shortly after casting his own ballot, Montenegro told reporters he was confident stability could be achieved.

“There is a search for a stable solution, but that will now depend on [people’s] choices,” he said.

A second consecutive minority government in Portugal would dash hopes for an end to the worst spell of political instability in decades for the European Union country of 10.6 million people.

For the past 50 years, two parties have dominated politics, with the Social Democrats, who head the DA, and the Socialist Party alternating in power.