WASHINGTON (AP) – Senate Minority Leader Mitch McConnell says he will not again help Democrats extend the government’s borrowing authority. His warning raises fresh doubts about how Congress will avert a federal default when a temporary patch expires in December. The Kentucky Republican issued his warning in a letter to President Joe Biden a day after the Senate approved a $480 billion boost in the federal debt limit, enough to last about two months. McConnell was among 11 GOP senators who provided decisive support Thursday for a procedural move that opened the door for subsequent Senate passage of that measure with only Democratic support.