This choice decreed the success of the company and its rapid dimensional growth: Marelli was responsible for the technical aspects of production, while the young Benni soon took charge of the organizational and commercial management.

To guarantee a large market and create an efficient network of representatives, starting from 1900 he made numerous trips to Europe and Latin America.

Starting from 24 January 1935, Benni held the position of Minister of Communications on behalf of the fascist government of Benito Mussolini.

After 8 September he refused to join the Italian Social Republic and indeed, on the night of 20 August 1944, while he was in Stresa, he was arrested together with his wife by fascist agents under the orders of the prefect of Novara.

To escape both the persecution of fascist agents and the threats of anti-fascist partisans, Benni emigrated to Switzerland before the end of the conflict.