Leaders of Italy's populist Five Star Movement (M5S) urged party members Thursday to support a national unity government led by former European bank chief Mario Draghi, as they began voting on whether to join him.
Securing the approval of the M5S, the biggest party in parliament, is the final hurdle faced by Draghi before he can take over as prime minister, potentially as early as Friday.
But the party, which began life as an anti-establishment movement, is agonising over whether to back a quintessentially elite figure like the former European Central Bank (ECB) chief.
An online poll of M5S members was postponed from Wednesday to Thursday after its leaders claimed to have secured key commitments from Draghi, including on environmental and welfare policy.
Voting runs from 10am to 6pm (0900-1700 GMT), with results expected after 7pm.
"I AM VOTING YES, because there is no majority without us. I AM VOTING YES, because we have to defend what we have built for Italy," outgoing Foreign Minister Luigi Di Maio wrote on Facebook.
The speaker of the lower house of parliament Roberto Fico, another leading M5S figure, also said he would vote for Draghi, and party founder Beppe Grillo is equally in favour.
The ex-ECB president would probably be able to form a government even without the M5S, as nearly all other parties have rallied behind him, including the far-right League of Matteo Salvini.
But Federico Santi, an analyst at Eurasia Group, noted that "committed backing from M5S - the largest party in parliament - is important for him to set off with the broadest possible parliamentary majority, and to be less dependent on (Salvini)."
Commentators have suggested Draghi could announce a new cabinet and be sworn in by the end of the week, and seek votes of confidence in parliament on Monday and Tuesday.
His immediate tasks are expected to be speeding up coronavirus vaccinations plans and drawing up an economic reform plan linked to European Union relief funds.
Italy has been devastated by the coronavirus pandemic that plunged the country into its worst recession since World War II and claimed more than 92,000 lives.
But the country also expects to receive more than €200 billion in EU loans and grants, a huge windfall for its virus-stricken economy.
Getting a say on how to spend that cash is an obvious attraction for parties to join the government, even as part of a hotchpotch coalition.
Italy has been without a fully functioning government for almost a month since the collapse of prime minister Giuseppe Conte's previous administration.