Volunteers in Des Moines make calls at the campaign headquarters of then-Democratic presidential hopeful Sen. Barack Obama on Dec. 5, 2007 ahead of the Iowa caucus. Obama has called those "fired-up" campaign workers from his 2008 campaign, one of his proudest legacies.
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Arizona Cardinals fans wear masks of Presidential candidates Donald Trump and Hillary Clinton during the NFL game between the New York Jets and Arizona Cardinals Oct. 17, 2016.
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Donald Trump delivers a speech as he officially opens his Trump Turnberry hotel and golf resort in Scotland on Friday. Donald Trump hailed Britain's vote to leave the EU as "fantastic" shortly after arriving in Scotland.
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In 1999, then-Rep. John Kasich rode a dog sled after participating in the World Championship Sled Dog Derby award ceremony in Laconia, N.H. When he ran an "exploratory" campaign back then, few people knew who he was.
Thomas Checkler, owner of The Old Village Barber in Worthington, Ohio, discusses the impact that the barrage of political ads have on him and his customers during the 2012 presidential election campaign.
Addressable TV advertising technologies, which allow advertisers to selectively target audiences and serve different ads within them, are poised to play a bigger role in political campaigns.