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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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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Donald Trump arrives at the Republican National Committee headquarters on Capitol Hill last week to meet with House Speaker Paul Ryan and other GOP leaders. Nicholas Kamm/AFP/Getty Images hide caption

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'Highly Sophisticated Killers' No More. Trump Embraces Big Donors
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A voter enters a polling place on May 3 in Whiting, Ind. Older voters feel that the issues that concern them haven't been mentioned enough on the campaign trail. Scott Olson/Getty Images hide caption

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Older Voters To Candidates: Don't Forget About Us
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Donald Trump is seen in New York in 1991, the year of a phone call in which Trump allegedly posed as his own spokesman. The presidential candidate denied it was him after The Washington Post published the recording. Luiz Ribeiro/AP hide caption

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House Speaker Paul Ryan of Wisconsin meets with reporters on Capitol Hill in Washington on Thursday after his meeting with Republican presidential candidate Donald Trump. Cliff Owen/AP hide caption

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Republican presidential candidate Donald Trump arrives for a meeting with House Speaker Paul Ryan at the Republican National Committee Headquarters on Capitol Hill Thursday. Andrew Harnik/AP hide caption

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A demonstrator holds a "Stop Trump 2016" sign across the street from an April 25 Donald Trump rally, in West Chester, Pa. Bloomberg/Bloomberg via Getty Images hide caption

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Progressive SuperPACs Ramp Up Their Big-Money Effort Against Donald Trump
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Attorney William Johnson, a leader of the American Freedom Party and self-proclaimed white nationalist, made it onto Trump's list of delegates. He now says he will not attend the convention. Jae C. Hong/AP hide caption

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