“ There is no showing of lack of diligence on appellant's part. Under the present circumstances the absence of an opinion by the Maryland Court of Appeals is no reason for refusing consideration here. Whatever the Maryland court may later say, appellant has been deprived of his opportunity to become a candidate in the election.
No. 372 is a petition for writ of certiorari from the same order of the Court of Appeals insofar as it reversed the dismissal by the Circuit Court of the petition for writ of mandamus brought by a Progressive Party nominee for the United States House of Representatives. ”

“ Green, supra; Cook v. Fortson, Turman v. Duckworth, supra; South v. Peters, 339 U.S. 276, 70 S.Ct. 641. Where, as here, a justiciable controversy and substantial federal questions coexist, the court can and should advance a determination of the case. ”