How can indirect lobbying activities be influential?

Indirect lobbying or grassroots lobbying is the act of lobbying through requesting the people to call on government officials and legislators to act on important issues rather than directly meeting the officials.  They make use of several methods to get public to call government’s attention to their interest.  In this modern age, they now make use of internet through social media and emailing as well as calling residents to take action.  Then there is the use of advertisements on television and radio.  Others may be through social functions and meetings or activities where they try to get the people’s support.