Senate Republicans on the spot over Trump comments on Khan

The uproar over Donald Trump's criticism of a bereaved Army family put vulnerable GOP senators in a tight spot, underscoring anew the political challenges created for Republicans by their newly minted presidential nominee. And with the general election campaign now squarely underway, the firestorm over Trump's attacks on the Khan family is likely just a taste of trials to come as Republicans negotiate how closely to align with their volatile nominee.