Donald TrumpRICHMOND, Va. (AP) _ Donald Trump has blasted the Republican Party of Virginia via Twitter for its plan to require that 2016 primary voters sign a statement confirming they are Republicans. According to media outlets, Trump says the requirement could discourage independent and first-time voters from casting primary ballots in Virginia, where primaries are open to all registered voters. In one of a series of tweets, Trump wrote that the requirement is a “suicidal mistake.”   The Virginia State Board of Elections certified Dec. 16 that voters in the Mar. 1 Republican presidential primary will have sign a form that says: “My signature below indicates that I am a Republican.”   Virginia GOP Executive Director John Findlay said earlier this month that the requirement is a sensible step to ensure that Republican voters pick the Republican nominee.