Definition of Campaign
What is the definition of the term "campaign"? What is meant by the word "campaign"?
A campaign is a concerted and coordinated effort to win some sort of office, political or otherwise.
For instance, Joe Smith wants to run for mayor of the small town that he lives in, and he decides to launch a "campaign" to become mayor. This could include posting signs around town, going door-to-door to talk to constituents and placing ads in the local newspaper.

When somebody drops out of a race, they are said to have "suspended their campaign". This is just a nice way of saying that they have dropped out of the race.
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