A series of military operations undertaken to achieve a large-scale objective during a war: Grant's Vicksburg campaign secured the entire Mississippi for the Union.
An operation or series of operations energetically pursued to accomplish a purpose: an advertising campaign for a new product; a candidate's political campaign.
To engage in an operation planned to achieve a certain goal: campaigned through the jungles of Vietnam; campaigned for human rights.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.