Former Florida Gov. Jeb Bush poses with supporters for photos during a fundraiser in May. Alan Diaz/AP hide caption

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Sen. Ted Cruz, R-Texas, apologized Wednesday after making a joke about Joe Biden while the vice president was mourning the death of his son. Charles Dharapak/Associated Press hide caption

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Wisconsin Gov. Scott Walker offers cheese and ice cream to guests in his hospitality room at the Iowa Lincoln Day Dinner in Des Moines on Saturday. Charlie Neibergall/AP hide caption

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Republican presidential hopeful Sen. Ted Cruz speaks at the Republican Leadership Summit Saturday in Nashua, N.H. Jim Cole/AP hide caption

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Polls show changing American opinion on marijuana, and it's having an effect on politics. Leon Neal/AFP/Getty Images hide caption

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Sen. Rand Paul, R-Ky., center, meets with members of the Londonderry Fish and Game Club in Litchfield, N.H., on Jan. 14. Paul was one of three GOP presidential hopefuls who attended Sunday's semiannual gathering of David and Charles Koch's donor network in California. Jim Cole/AP hide caption

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Sen. Rand Paul takes the stage at the Conservative Political Action Conference in National Harbor, Md., Friday. For the second consecutive year, Paul won the event's straw poll. Chip Somodevilla/Getty Images hide caption

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