Former President Bill Clinton plays with balloons onstage at the end of the fourth day of the Democratic National Convention at the Wells Fargo Center in Philadelphia in July.
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Tim Kaine (left) and Mike Pence take questions from moderator Elaine Quijano during the vice presidential debate at Longwood University in Farmville, Va., on Tuesday.
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A producer walks past a lectern on the stage of the first presidential debate. The vice presidential debate is Monday night between Democrat Tim Kaine and Republican Mike Pence.
Gov. Mike Pence, R-Ind., and Sen. Tim Kaine, D-Va., will face off Tuesday evening during this campaign's only vice presidential debate, at Longwood University in Farmville, Va.
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L: Republican vice presidential nominee Mike Pence speaks at a campaign rally Aug. 31 in Phoenix. R: Democratic vice presidential nominee Tim Kaine speaks at a campaign event Aug. 1 in Richmond, Va.
L: Ralph Freso R: Alex Wong/Getty Images
Richard M. Nixon with Checkers, his family's cocker spaniel, in 1952. Nixon, who was then the Republican vice presidential nominee, mentioned Checkers in a TV-radio report on his finances.
Hillary Clinton attends church with daughter Chelsea Clinton at the Greater Mount Carmel Missionary Baptist Church in St. Louis, Missouri while on the campaign trail in 2008.
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Ever since New Jersey Gov. Chris Christie endorsed Trump (and stood behind him at a Super Tuesday event), he has been on many people's lists of likely Trump running mates.
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