How many people calling a member of Congress does it take to sway their vote or make them change how they feel about a bill?

It takes 3 to 4 people to call a member of Congress to make them change their vote or to educate them on what they think.  You can see how important it is that you get out there when a bill is put up to educate your members in Congress on legislation.  They have so many bills coming at them they are all not able to read and understand what is written in each bill.  These bills affect US!