influence-n; 3 Senses

Sense Number 1: the power or capacity to be a contributing cause or effector

Commentary: INFLUENCE[+quality][+ability][+causal][+contributing] [+relation][+role][+factor][+contributing] The power to affect people or events
NOTE: The capacity to influence is possessed by some NP(agent) in the sentence
NOTE: X's influence, X has influence, X of influence

Lobbies and special interests have too much influence in the government.
John used his parents' influence to get the job.
Labor unions had the greatest influence during the Depression.
I'm embarrassed to admit how much influence my wife has over me.
Mary's influence caused me to vote for Bush in the last election.
That nation could project its sphere of influence across the globe.

PropBank: influence.01
WordNet 3.0 Sense Numbers: 1

Sense Number 2: something (often someone) that is a contributing cause

Commentary: INFLUENCE[+entity][+agent][+causal]
NOTE: refers to a thing or person
NOTE: X BE influence,

My mother was a powerful influence in my life.
Mary suspected that John was a bad influence on her children.
The author said his biggest influences were Kurt Vonnegut and William Shakespeare.
Scientists are studying how big an influence increased levels of carbon dioxide are on global weather patterns.
One influence on the Prime Minister's decision is the recent economic growth of Poland.

PropBank: influence.01
WordNet 3.0 Sense Numbers: 1

Sense Number 3: The effect on something, result or consequence

Commentary: INFLUENCE[+event][+state][+resulting][+behavior][+shaped][+externally] The resulting effect that an entity or event has on another.
NOTE: the patient NP of the influence (effect) is always mentioned (this is not true for Sense 1)

My mother's wishes had a great influence on my career choices.
They tried to exert some influence on the outcome of this election.
The study was inconclusive about the influence of television violence on teen conduct.
European culture has always had a strong influence on America.
John was "under the influence" when he drove home that night.

PropBank: influence.01
WordNet 3.0 Sense Numbers: 1