The cause was temporal frontal lobe dementia, his sister, Susan Phillips Bari, said. Along with Richard Viguerie, Paul Weyrich, Terry Dolan and others, Mr. Phillips was a leader of the New Right, a movement that gave more clout to the right wing of the Republican Party in the 1970s and ’80s, much as the Tea Party has in recent years. Even among stalwart conservatives, Mr. Phillips was known for being especially devoted to the ideological principles of the right, including limited government, traditional family values, strong national defense and opposition to abortion. “He was our true north,” Mr. Viguerie, famed for pioneering the political use of direct mail, said in an interview on Monday. “You could compromise on strategy, but on principle Howie was unswerving.” Mr. Phillips’s integrity as a conservative was on display in President Richard M. Nixon’s administration. In early 1973, the president signaled his intention to withhold financing from the Office of Economic Opportunity, an antipoverty agency with roots in President Lyndon B. Johnson’s war on poverty. The president named Mr. Phillips acting director and charged him with dismantling it. “I believe Richard Nixon epitomizes the American dream and represents all that is great in America,” Mr. Phillips said at the time. Nixon was unable to carry out his plans, however, after Democrats successfully sued to prevent him from starving an agency that Congress had authorized. And when Nixon yielded and continued to finance Johnson’s Great Society programs, Mr. Phillips considered the president to have broken his word and resigned. “The thing that changed him was that while he was working for O.E.O., before he became acting director, he went around the country looking at all the grantees,” Ms. Bari, his sister, said, and concluded that much of the money was supporting liberal advocacy groups. “Not to what the taxpayers thought they were supporting,” Ms. Bari said. “That’s what radicalized him.” In 1974, Mr. Phillips founded the Conservative Caucus, an advocacy group, based in Warrenton, Va. He stepped down as its chairman in 2011. Mr. Phillips could be a thorn in the side of presidents, even fellow Republicans. He lobbied against President Ronald Reagan’s nomination of Sandra Day O’Connor to the Supreme Court and against the first President George Bush’s nomination of David Souter to the court, arguing that they would favor abortion rights. “Whether he won or lost, he always said that what is right is what he was going to do,” Charles Orndorff, the administrative vice president of the Conservative Caucus, said in an interview on Monday. “His honor, as a conservative leader, meant the most to him.” In 1990, believing that neither major party would enact the policies he favored, Mr. Phillips led the formation of the U.S. Taxpayers Party (later renamed the Constitution Party), which declares that its policies are based on the founding documents of the nation and the original intent of the founding fathers. He was its candidate for president in 1992, 1996 and 2000. His best showing was in 1996, when he received one-fifth of 1 percent of the vote. Howard Jay Phillips was born in Boston on Feb. 3, 1941, and grew up in nearby Brighton, Mass. His father, Frederick, ran an insurance agency; his mother, the former Gertrude Goldberg, was a homemaker. Though he was raised Jewish, he became a Christian in the 1970s. He was present at the 1960 conference at the home of William F. Buckley Jr. in Sharon, Conn., that created the conservative organization Young Americans for Freedom. Mr. Phillips graduated from Harvard in 1962. In the mid-1960s he was chairman of the Boston Republican Committee, and in 1968 he managed the Senate campaign of Richard S. Schweiker, a Pennsylvania Republican congressman who unseated Senator Joseph S. Clark, a Democrat. Mr. Phillips worked in several positions in the Nixon administration before landing at the Office of Economic Opportunity. Somewhat quixotically, he sought the Democratic nomination for senator from Massachusetts in 1978 in order to oppose the Republican incumbent, Edward W. Brooke III, a defender of Great Society programs. Mr. Phillips lost in a primary to Paul Tsongas, who went on to defeat Senator Brooke. In addition to his sister, Mr. Phillips is survived by his wife, the former Margaret Blanchard, whom he married in 1964; three sons, Douglas, Bradford and Samuel; three daughters, Elizabeth Lants (known by her middle name, Amanda), Alexandra and Jennifer; and 18 grandchildren. On Monday, Mr. Viguerie recalled the occasional derision that he and Mr. Phillips endured for their political ardor. “He and I did an interview with Dan Rather at the G.O.P. convention in 1984, and Rather asked us about George H. W. Bush, and we were very critical of his conservative credentials,” Mr. Viguerie said. “And the next night, Rather had Bush on, and he said, ‘Richard Viguerie and Howard Phillips say you’re not a conservative. Well, Mr. Vice President, what about it? Are you a conservative?’ “And he said, ‘Yes, Dan, I’m a conservative, but I’m not a nut about it.’ ”
