Though they have no intention of ending the United States’ close alliance with Israel, a growing number of Democrats in Washington say they are no longer willing to give the country a pass for its harsh treatment of the Palestinians and the spasms of violence that have defined the conflict for years. Underscoring how skepticism around the campaign in Gaza had spread to even some of Israel’s strongest defenders in Congress, Representative Gregory W. Meeks of New York, the chairman of the Foreign Affairs Committee, told Democrats on the panel on Monday that he would ask the Biden administration to delay a $735 million tranche of precision-guided weapons to Israel that had been approved before tensions in the Middle East boiled over... Another sign of the evolution came over the weekend from Senator Bob Menendez, Democrat of New Jersey and the chairman of the Foreign Relations Committee. Mr. Menendez is known as one of Israel’s most unshakable allies in the Democratic Party, which he bucked to oppose President Barack Obama’s 2015 nuclear deal with Iran based on Israeli opposition. Yet on Saturday, as the death toll mounted in Gaza and southern Israel, Mr. Menendez issued a stern statement saying he was “deeply troubled” by Israeli strikes that had killed Palestinian civilians and the tower housing news media outlets. He demanded that both sides “uphold the rules and laws of war” and find a peaceful end to fighting that has killed more than 200 Palestinians and 10 Israelis.