ROME — Populist, anti-establishment parties were the big winners of Sunday’s Italian election, raking in a combined total of more than 50 percent of the vote.

Early results indicate the country may be headed for a hung parliament or drawn out negotiations, with no single party or coalition garnering enough votes to govern alone.

The anti-establishment 5Stars led by 31-year-old Luigi Di Maio is likely to emerge as the largest party, with over 30 percent of the vote. That would signal major gains for the group, which has tried to appeal to voters disaffected with traditional Italian politics.

“That would mean the 5Star Movement will be the pillar of the next legislature,” said Alfonso Bonafede, a 5Star lawmaker, hailing it as an “extraordinary” result if confirmed.

The biggest upset is the emergence of the Matteo Salvini’s far-right League (formerly the Northern League) as the most popular force on the right. The League was headed for about 18 percent of the vote, making it the country’s third-largest party.

Its share of support also makes it by far the largest member in a right-wing alliance with former Prime Minister Silvio Berlusconi’s Forza Italia and the far-right Brothers of Italy. The coalition is expected to receive about 37 percent of the vote, according to projections as the official results come in — short of the 40 percent needed to avoid a hung parliament.

If confirmed, the result would give Salvini a stronger claim to be prime minister than the man chosen by 81-year-old Berlusconi to rule in his place (the media tycoon is barred because of a fraud conviction), the current European Parliament President Antonio Tajani. Such a result would be a dramatic turnaround from previous coalitions between the two forces, which were always dominated by Forza Italia.

“What interests us is reaching 40 percent with our coalition and winning, so we don’t consider these preliminary results a victory yet,” said Gianmarco Centinaio, a senator for the League.

While the 5Stars previously pledged not to enter a coalition with any party, Di Maio said in January that if the party fell short of 40 percent of votes, he would put forward his program and see what other parties, including the League, would be willing to back it.

Meanwhile the governing center-left Democratic Party (PD), led by former Prime Minister Matteo Renzi, is expected to receive about 19 percent of the vote.

With Italy using a new electoral system, the official results could differ substantially from the exit polls that were released after voting ended at 11 p.m. If no group hits the 40 percent threshold considered the safety net for avoiding a hung parliament, they may have to seek alliances to convince President Sergio Mattarella they can form a majority.

Anti-euro sentiment

A strong showing by the League, which has an anti-immigrant agenda, would force the issue even higher up the political agenda. Berlusconi described immigration as "a social bomb ready to explode" after a right-wing extremist attacked six Africans last month, and right-wing candidates have presented rival promises to deport illegal immigrants.

Renzi's PD appears to have been punished by voters for the slow pace of economic recovery and the persistently high unemployment rate. With early projections giving the PD around 20 percent — half its showing at its peak in the 2014 European elections — it could be hard for 43-year-old Renzi to survive.

“If this is the final result it’s clearly a negative figure for the Democratic Party and we will become the opposition,” said the PD's leader in the lower house, Ettore Rosato, on TV.

Unlike the pro-EU PD and Forza Italia, the League and 5Stars have Euroskeptic leanings although they largely toned them down during the election campaign. However a bigger concern for European Commission President Jean-Claude Juncker, according to words he later had to withdraw, is that Italy gets a “non-operational government.”

Wolfango Piccoli, head of consultancy firm Teneo Intelligence, said the exit polls pointed to “a badly hung parliament with no majority for a grand coalition and where the anti-euro parties gathered almost 50 percent of the votes.”

Neither is the prospect of fresh elections very encouraging, according to analysts like Francesco Clementi, a professor of Comparative Public Law in Perugia, who said another vote under the new electoral law "will produce the same results."

The first signs of potential governing majorities will emerge from March 23 when the 630 MPs and 315 senators gather to elect the presidents of both chambers.

Anna Momigliano contributed to this article.