Question: Who was the chief economic policy adviser during the 2008 presidential campaign of the current US Senator from Arizona?
Context: Jeffrey B. Liebman (born c. 1967) is an American economist who served as the executive associate director and chief economist and then as the acting deputy director for policy of the Office of Management and Budget within the Obama Administration.  During the 2008 Presidential Campaign he served as a top economic advisor to the presidential campaign of Democratic Senator Barack Obama of Illinois. The 2008 presidential campaign of John McCain, the longtime senior U.S. Senator from Arizona, was launched with an informal announcement on February 28, 2007 during a live taping of the "Late Show with David Letterman", and formally launched at an event on April 25, 2007.  His second candidacy for the Presidency of the United States, he had previously run for his party's nomination in the 2000 primaries and was considered as a potential running mate for his party's nominee, then-Governor George W. Bush of Texas.  After winning a majority of delegates in the Republican primaries of 2008, on August 29, leading up to the convention, McCain selected Governor Sarah Palin of Alaska as his running mate for Vice President.  Five days later, at the 2008 Republican National Convention, McCain was formally selected as the Republican Party presidential nominee in the 2008 presidential election. Douglas James "Doug" Holtz-Eakin (born February 3, 1958) is an American economist.  He was formerly an economics professor, Director of the Congressional Budget Office, and chief economic policy adviser to United States Senator John McCain's 2008 presidential campaign.  Holtz-Eakin is currently president of the American Action Forum policy institute, a conservative think tank. Sir David Edward John Ramsden CBE (born 9 February 1964) is a senior British civil servant, serving as the Chief Economic Adviser to HM Treasury.  He is the Head of the Government Economic Service, having previously served as Joint Head of the Service with Vicky Pryce, formerly Chief Economic Adviser and Director-General at the Department for Business, Innovation and Skills. Marco Antonio Lopez (born April 7, 1978) is an Arizona politician.  He has served in both elected and non-elected public offices, including Mayor of Nogales, Arizona, Executive Director of the Arizona-Mexico Commission, Policy Adviser to Governor Janet Napolitano for Mexico and Latin America, and Senior Adviser for International Affairs to the Governor.  Born in Nogales, Sonora, Mexico, and raised in Nogales, Arizona, United States, he graduated from the University of Arizona.  Lopez served at the Arizona State Capitol as Director of the Arizona Department of Commerce appointed by Arizona Governor Janet Napolitano.  With the Homeland Security Nomination made for Napolitano.  Lopez was appointed to serve as the Chief of Staff for United Customs and Border Protection. Paul William Bucha (born August 1, 1943) is an American Vietnam War veteran and recipient of the Medal of Honor.  He was a foreign policy adviser to Barack Obama's 2008 presidential campaign. John Sidney McCain III (born August 29, 1936) is an American politician who currently serves as the senior United States Senator from Arizona, in that office since 1987.  He was the Republican nominee for President of the United States in the 2008 election, which he lost to Barack Obama. NGP VAN is a privately owned American company specializing in helping progressive campaigns and organizations leverage technology to meet their goals.  In 2009, the company was the largest partisan provider of campaign compliance software, used by most Democratic members of Congress.  The company's services have been utilized by clients such as the Obama 2008 presidential campaign, the Obama 2012 presidential campaign, the Bernie Sanders 2016 presidential campaign, the Hillary Clinton 2016 presidential campaign, the British Liberal Democrats, and the Liberal Party of Canada.  Its current president and CEO, Stuart Trevelyan, was a veteran of the 1992 Clinton-Gore "War Room", providing research, analysis, and whip counts to the Clinton Administration as a member of the White House Office of Legislative Affairs. Kevin Allen Hassett is an American economist and the Chair of the Council of Economic Advisers.  He is known for his work on tax policy and for coauthoring the book "Dow 36,000", published in 1999.  Prior to becoming Chair of the Council of Economic Advisers, Hassett was the State Farm James Q. Wilson Chair in American Politics and Culture and Director of Research for Domestic Policy at the American Enterprise Institute, a conservative think tank.  He was John McCain's chief economic adviser in the 2000 presidential primaries and an economic adviser to the campaigns of George W. Bush in the 2004 presidential election and McCain in the presidential election of 2008.  He was among Mitt Romney's economic advisers for the 2012 presidential campaign. The Office of the Chief Trade Adviser (OCTA) is an independent trade advisory body of the Forum Island Countries.  OCTA provides policy advice and capacity building support to the Forum Island Countries, particularly in the Pacific Agreement on Closer Economic Relations (PACER) Plus trade negotiations with Australia and New Zealand.  OCTA was established on 29 March 2010 and is based in Port Vila, Vanuatu.  The first to be appointed to the Chief Trade Adviser position was Chris Noonan, an academic from New Zealand.  Noonan resigned in September 2011.  The OCTA Governing Board then appointed Julia Tijaja, the Trade Policy Adviser, as Caretaker Chief Trade Adviser in the interim until the new Chief Trade Adviser came on board.  In February 2012, Edwini Kessie, an international trade law expert, was appointed the new Chief Trade Adviser.  Kessie took up his post in June 2012.  Thirteen Forum Island Countries are currently members of the OCTA; Cook Islands, Federated States of Micronesia, Kiribati, Nauru, Niue, Palau, Papua New Guinea, Marshal Islands, Samoa, Solomon Islands, Tonga, Tuvalu and Vanuatu.  OCTA is fully owned and is under the exclusive control of its members.
Answer: Douglas James "Doug" Holtz-Eakin