Question for the legal types out there:
Is this legal?

Va. GOP to require loyalty oath in presidential primary

RICHMOND, Va. —

At the request of the Virginia Republican Party, the State Board of Elections voted 3-0 today to close the March 6 presidential primary and require a loyalty oath for participation.

That means anyone who wants to vote must sign a form at the polling place pledging to support the eventual Republican nominee for president. Anyone who refuses to sign the pledge will be barred from voting.