Donald Trump stands with some of the delegates from North Dakota, who elevated him over the 1,237 needed for the GOP nomination. Charles Rex Arbogast/AP hide caption

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Meet The Unbound Delegates Who Helped Donald Trump Secure The Nomination
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Ahead of the California primary, Sen. Bernie Sanders speaks at a campaign rally at Ventura College on May 26, 2016 in Ventura, California. The David McNew/Getty Images hide caption

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Republican presidential candidate Donald Trump was a guest on Jimmy Kimmel Live on Wednesday. Randy Holmes/ABC via Getty Images hide caption

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Politics Podcast: It's For Real Now — Trump Is The Presumptive GOP Nominee
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TSA Administrator Peter Neffenger prepares to testify during a House Homeland Security Committee hearing on Capitol Hill. Lawmakers sought answers as to why long security lines persist at airports around the country. Mark Wilson/Getty Images hide caption

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TSA Hopes To Speed Up Screening Lines This Summer, Administrator Tells Congress
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One month after the atomic bomb was dropped on Hiroshima, a correspondent stands amid ruins left by the explosion. The structure seen standing became the Hiroshima Peace Memorial, which President Obama will visit Friday. AP hide caption

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Protesters help a fellow demonstrator who was affected by the smoke and pepper spray reportedly used by police to disperse the crowd outside Tuesday's rally for Republican presidential candidate Donald Trump in Albuquerque, N.M. Russell Contreras/AP hide caption

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Televisions display a political ad from 2011 in Iowa. Chip Somodevilla/Getty Images hide caption

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Do TV Attack Ads Work Anymore?
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Donald Trump made a stop in Lawrenceville, N.J., last week and is heading out to several more states that vote on June 7. Eduardo Munoz Alvarez/AFP/Getty Images hide caption

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Trump To Campaign In Final Primary States, Raising Cash Along The Way
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Sen. Bernie Sanders, an independent from Vermont, speaks during a campaign event in Los Angeles, Calif., on March 23. Patrick T. Fallon/Getty Images hide caption

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Making Democrats' Primaries More Open Could Be Harder Than You Think
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Democratic presidential candidate Bernie Sanders addresses a rally Wednesday at the Santa Clara County Fairgrounds in San Jose, Calif. The senator's campaign is intently focused on a big win in the state on June 7, and has poured money into TV ads there. Josh Edelson/AFP/Getty Images hide caption

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Hillary Clinton addresses a town hall hosted by the AFL-CIO in Detroit in 2007. During the 2008 campaign, Clinton said the U.S. should take a timeout on trade deals after supporting NAFTA in the 1990s. Carlos Osorio/AP hide caption

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Evolution Or Expediency? Clinton's Changing Positions Over A Long Career
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