Italian lawmakers have begun voting to elect a new president.

Though the post is largely ceremonial it is being seen as a test for Prime Minister Matteo Renzi, who has named a constitutional court judge to replace George Napolitano who resigned earlier this month.

The first round failed to secure a majority and could to go up to several rounds. A fourth round on Saturday is expected to seal victory as only a simple majority is required.

The nomination of 73-year-old Sergio Mattarella has angered opposition rival Silvio Berlusconi, who says that Renzi has broken a pact on reforms by not proposing a joint candidate.

However, Mattarella won unanimous support from Renzi’s party, as they oppose the reform alliance with Berlusconi. The Prime Minister will have to look for support among some of the parliament’s smaller parties

A lot is riding on this vote for the premier and the rest of the country. A prolonged fight with Berlusconi could put their pact in jeopardy and raise the spectre of early elections.