The 1758 papal conclave (May 15 – July 6), convoked after the death of Pope Benedict XIV, elected Cardinal Carlo Rezzonico of Venice, who took the name Clement XIII.

Because of the absence of the political representatives of the main Catholic courts the ambassadors of France and the Empire asked the electors for delay voting until their arrival.

In particular Corsini worked vigorously for the election of Giuseppe Spinelli, leader of the Zelanti, but met with the strong opposition of Orsini, Cardinal Protector of the Kingdom of Naples.

But after that ballot Cardinal Luynes informed the Dean of the Sacred College Rainiero d’Elci of the official veto of the King of France against Cavalchini.

[7] The exclusion met with strong protests, but Cavalchini himself said, "It is a manifest proof that God deems me unworthy to fill the functions of his vicar upon earth".

[8] After the collapse of Cavalchini's candidacy, Portocarrero advanced as a new candidate Paolucci, but he was rejected by French, who – together with the faction of Corsini, voted again for Crescenzi.

Direct negotiations between von Rodt and Spinelli resulted in the proposal for election of the Venetian Cardinal Carlo Rezzonico, bishop of Padua.

[10] On July 6 in the evening Carlo Rezzonico was elected Pope, receiving thirty-one votes out of forty-four, one more than the required majority of two-thirds.