NEW YORK - In their fifth one-on-one debate, Democratic hopefuls Hillary Clinton and Bernie Sanders showed the mounting pressure of their marathon White House race with a series of heated exchanges on several issues, notably the candidate's differing opinions on the Israeli-Palestinian conflict.The last nine opinion polls taken in New York, a state where Sanders was born and Clinton served eight years as a US senator, show her holding a double-digit advantage over him ahead of Tuesday's New York vote, the next nominating contest on the road to a July national convention and the Nov. 8 election.The two candidates battled over support for Israel, with Sanders calling himself "100 percent pro-Israel" but adding that Middle East peace required treating "the Palestinian people with respect and dignity."He questioned what he said was Clinton's too-firm commitment to Israeli Prime Minister Benjamin Netanyahu."There comes a time if we are going to pursue justice and peace that we are going to have to say that Netanyahu is not right all of the time," Sanders said.Clinton responded neutrally. "Nobody is saying that any individual leader is always right but it is a difficult position," she said."Describing the problem is a lot easier than trying to solve it," Clinton said, touting her experience as secretary of state in trying to settle the Israeli-Palestinian dispute.While far short of the brawls that have characterized Republican debates, the tone reflected a more contentious turn in the Democratic race.Earlier on Thursday, Sanders denounced as "inappropriate and insensitive" a warm-up speaker's call at a Manhattan rally for Sanders on Wednesday to stop electing "corporate Democratic whores," a remark seemingly aimed at Clinton.Sanders, 74, has won seven of the last eight state Democratic nominating contests, but most of those were small states that did not help him cut Clinton's commanding lead in the race for the 2,383 delegates needed to win the nomination to represent the party in the Nov. 8 presidential election.Clinton leads Sanders by 251 bound delegates to the July nominating convention. Her lead balloons to almost 700 when the support of superdelegates - party leaders who are free to back any candidate - are added.Sanders faces a tough task cutting Clinton's lead since Democrats award delegates in each state proportionally to the candidate's level of support, allowing her to pile up delegates and draw nearer to the nomination even if she loses a state.Sanders has pledged to battle all the way to the party's July convention in Philadelphia, arguing superdelegates will switch to him once they realize the extent of his popular support. Clinton so far has 2.4 million votes more than Sanders in the state-by-state nominating race. As the two-hour debate ended, the Brandwatch company which analyzes social-media sentiment said Sanders had more than 173,000 mentions on Twitter, 55 percent of them positive, while Clinton had more than 191,000 mentions, 54 percent of them negative.Sanders, who had questioned the former secretary of state's qualifications to be president, conceded she was qualified but said she had shown poor judgment by taking money from Wall Street for speeches she gave, by voting as a US senator to back the 2003 Iraq invasion and by supporting free trade deals."Does Secretary Clinton have the intelligence, the experience to be president? Of course she does but I do question her judgment," Sanders said at the debate in the New York borough of Brooklyn."I question her judgment which voted for the war in Iraq, the worst foreign policy blunder in the history of this country," he said. "I question her judgment about running Super PACS that are collecting tens of millions of dollars from special interests ... I don't believe that is the kind of judgment we need."Clinton, 68, responded the charges were also an attack on President Barack Obama, who as a candidate raised money on Wall Street and utilized Super PACS, outside funding groups that can raise unlimited sums of money, but still fought for tough regulations on the financial services industry."This is a phony attack that is designed to raise questions when there is no evidence or support," she said.The debate took place at the historic Brooklyn Navy Yard, a sprawling facility now home to artists and businesses, including a distillery and a film studio. Supporters on both sides strove to out-shout one another from beginning to end.