Mandate
In politics, a mandate is the authority granted by a constituency to act as its representative.
The concept of a government having a legitimate mandate to govern via the fair winning of a democratic election is a central idea of democracy. New governments who attempt to introduce policies that they did not make public during an election campaign are said to not have a legitimate mandate to implement such policies.
Elections, especially ones with a large margin of victory, are often said to give the newly elected government or elected official a mandate to implement certain policies. Also, the period a government serves between elections is often referred to as a mandate and when the government seeks re-election it is said to be seeking a "new mandate".