PHILADELPHIA — The national and state Republican parties vowed Tuesday to oppose GOP Senate candidate David McCormick in his lawsuit seeking to have potentially hundreds of contested mail ballots counted in his neck-and-neck primary race against Mehmet Oz. But with a state-mandated recount looming, an undeterred McCormick pushed the state’s highest court to take up his case — even if that meant standing at odds with his party. At issue are several thousand mail ballots which arrived on time but were missing the required handwritten date on the outer envelope. Previously, they would have been r…
