WASHINGTON (AP) — 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.

Senate Republicans running for re-election weighed in one after another Monday to condemn Trump's repeated attacks on the parents of slain U.S. Army Capt. Humayun Khan, with former prisoner of war Sen. John McCain of Arizona leading the charge. And in an op-ed Tuesday, a New York congressman became the first House Republican to announce that he would vote for Democrat Hillary Clinton.

McCain issued a lengthy statement insisting that Trump has no right "to defame those who are the best among us" and pleading: "I hope Americans understand that the remarks do not represent the views of our Republican Party, its officers, or candidates."

Sen. Charles Grassley of Iowa said Trump's comments "are not in line with my own beliefs about how the members of the military and their families should be treated."

Sen. Richard Burr of North Carolina said that "Captain Khan is an American hero in every sense of the term and the Khans deserve our sincerest gratitude."