Based on your question that ask about how leader influenced there members in the congress and what factor that makes it difficult to be successfull. First leadership trait is Offering or Endorsing Financial Assistance, and also their political power may affect. The factor that makes it difficult is the limit.
Answer: Serial recall
Explanation:
Serial recall is a process where events that were done in the past are outlined in the by which they took place to get a knowledge of an event or what needs to be checked. It is used by investigation agents to get an idea of what they need to do on a case. Both I and my roommate would have to outline events individually that took place that day and match them up to know who's at fault.
The stellar evolution is the evolution or process of a star over time. Stars grow just like us. For example, stars are born and develop over time just like we do.
Hope this helps :)