Conservative vice-chairman Michael Fabricant said the party's voice was "muffled" and unclear following the defeat in the Eastleigh by-election.
The MP took to Twitter to argue that the party needed to "simplify its message":
#Eastleigh The Conservative voice is muffled and not crisp. It does not clearly project Conservative core policies or principles.
#Eastleigh The Cons Party must now co-ordinate & simplify its message without policy distractions away from core principles. 26 months
#Eastleigh Everyone from the PM downwards must focus on the economy, immigration, crime, Europe and not allow other side policies distract