Answer:
Foot-in-the-door
Step-by-step explanation:
Foot-in-the-door technique: In psychology, the term foot-in-the-door technique is referred to a phenomenon in which an individual initiate by agreeing for a small request and later on make the other person agree for a bigger request.
Example: In the question above, as a neighbor asks Shiloh to sign for a petition that supports a local politician (small request) and later on she is being asked to donate some amount (bigger request).