1.) a. identify and explain two ways party leaders (speaker of the house, president pro tempore of the senate, majority leaders, minority leaders, and whips) influence members of their party congress.
b. identify and explain one factor that makes it difficult for party leadership to influence members of their party in congress.
2. identify and explain three reasons for the incumbency advantage.

1. a.) The whip's position is to to "whip" a party member in line and vote the way the party would want the member to (that's one one example of influencing members of Congress). Secondly, the major party leaders will often personally call or meet with specific members of Congress to get legislation passed. The show, West Wing, demonstrates this exactly.

b.) One factor where it might be hard for party leadership to influence members of their party is if the legislation/issue in question may be highly unpopular with the constituents (the people who voted in the politician). Take for example, hypothetically, the Democratic Party leadership wants a Democratic Party congressman from Houston to vote for increased regulations on the oil industry. The people of Houston who elected this congressman may not support these regulations on the oil industry (let's just say they all have ties to the oil companies). If this congressman was to vote for the regulations, he would anger his constituents, who may then decide not to re-elect him in the next election. Thus that is one factor that may make it hard for party leadership to influence individual members, is that if that particular legislation is unpopular with voters back home.

2. Name recognition. If you're an incumbent, everyone knows who you are, don't need to become known to the community.
 
Preserve the status quo: if there is really nothing that the politician did wrong, or nothing too serious that the politician's party did, why would people try to "fix something that ain't broke"? Voting for the status quo is definitely a strong factor, especially in an election without many galvanizing issues.
 
More money: because they are incumbents, generally they will have more money to spend as they typically don't have to go through primary battles (elections to see who will represent the party in the state/congressional district).