MADRID • European leaders and economists are still locked in a heated debate about whether austerity policies have done more to help or hurt people in the region, particularly in Europe's heavily indebted south.

But as Sunday's election in Spain showed, voters seem to have made up their minds. A backlash against austerity has now clearly cracked the club of parties that had a lock on politics, and ushered in a new generation of challengers.

The outcome in Spain was messy and it could well take weeks of haggling among the parties to sort out who will be able to govern.

But, in a close approximation of the October election result in Portugal, a majority of Spaniards voted against what had been an austerity-minded government.

Those outcomes followed the repudiation of an austerity government in Greece early this year.

"The sense of political crisis in Spain and some other European countries is clearly the fruit of the economic crisis," said politics professor Jaime Pastor at the Universidad Nacional de Educacion a Distancia in Madrid.

The financial crisis, he argued, first put into question the viability of the region's economic model and welfare state, but eventually turned into "a debate over whether the cost of the crisis was shared fairly to which many voters answered negatively and are therefore demanding the removal of the crony capitalism of the big parties".

Still, Prime Minister Mariano Rajoy of Spain is hoping to stay in office, at the helm of a minority or coalition administration, after his conservative Popular Party won the most votes on Sunday but lost its parliamentary majority.

Even if he succeeds, some analysts say the shake-up of Spanish politics is irreversible after two emerging parties, Podemos and Citizens, made enough gains to lower the combined share of the two traditional parties, the Popular and the Socialist parties, to just over 50 per cent of the vote.

"Crises take place with a certain time lag, so it's clear the Spanish system of political parties has entered a transition, but not clear how long that transition will take," said Spanish political analyst Antonio Barroso at Teneo Intelligence, a think-tank in London. The returns also underlined a generational shift in regional politics.

Mr Rajoy, 60, tried to contrast his three decades in politics with the untested leadership of his three far-younger rivals, all of whom are in their 30s or 40s. It did him little good.

On Monday, Prime Minister Alexis Tsipras of Greece congratulated Podemos and its leader, Mr Pablo Iglesias, 37, on becoming the third-largest party in Spain, as well as the country's main anti-establishment force.

"Austerity has now been politically defeated in Spain, as well," said Mr Tsipras, 41, a role model for the rest of the European anti-establishment left.

In southern Europe, perhaps Italy alone has been spared the instability of a breakdown of its main party system.

But analysts note that Prime Minister Matteo Renzi's popularity has declined since he took office last year, as the public pressure for changes has not relented.

In Portugal, Socialist leader Antonio Costa, 54, survived a poor election result and then managed last month to snatch victory from the jaws of defeat after striking an improbable alliance with far-left, anti-establishment parties in order to oust the centre-right coalition that had won the most votes in the national election in October.

But even if more voters have rejected austerity, where this will take the region is uncertain.

As the result in Greece showed, even anti-austerity parties have to answer to financial markets and balance national budgets, and the numbers are still deeply stacked against the policies of the old left and their heavy spending on welfare states.

Among various scenarios for a possible coalition government in Spain, the only one that would ensure a parliamentary majority would be an alliance of Mr Rajoy's Popular Party and the opposition Socialists, led by Mr Pedro Sanchez.

"What came out of the ballot boxes is a monumental mess," Mr Bieito Rubido, editor-in-chief of the conservative newspaper ABC, told Spanish national television on Monday.

"Almost everybody has lost."

NEW YORK TIMES