Having joined Italy of Values (IdV) in 2000, he was elected to the Italian Senate in a by-election held in January 2005. He was elected to the Italian Chamber of Deputies in 2006 and re-elected in 2008. Since 2006 Donadi has been IdV floor leader in the Chamber.
- "Archived copy". Archived from the original on 2010-09-22. Retrieved 2010-09-30.CS1 maint: Archived copy as title (link)
- "L'IdV spacca il centrosinistra: «Alle Regionali andremo da soli» - Corriere del Veneto". corrieredelveneto.corriere.it. Retrieved 3 May 2018.