Question: What is the birthdate of this American politician, poet, and long time Congressman from Minnesota, whose campaign manager was Blair Clark?

Context articles: David Cobb
Tom Clements (politician)
Paulo de Morais
Rick Davis (politics)
Blair Clark
Great America PAC
Robby Mook
Mary Beth Cahill
Mindy Myers
Eugene McCarthy

David Keith Cobb (born December 24, 1962) is an American attorney, liberal political activist, campaign manager, and politician, who was the Green Party presidential candidate for the 2004 election.
 Cobb is also the co-founder of Move to Amend.
 Cobb later became the campaign manager for fellow Green Jill Stein for her presidential run in 2016.
Tom Clements (born 1951) is a South Carolina environmental activist and politician.
 Clements was the Green Party's nominee in the 2010 United States Senate election in South Carolina.
 Clements received more than 9% of the general election.
 He is the Southeastern Nuclear Campaign Coordinator for the US branch of Friends of the Earth in Columbia, South Carolina.
 Clements worked as the campaign manager for Democratic Congressman Doug Barnard, Jr. in the 1980s and as well as a long environmental activist with Greenpeace and the Nuclear Control Institute.
Paulo Alexandre Baptista Teixeira de Morais (born on 22 December 1963, in Viana do Castelo) is a Portuguese university professor and politician.
 He is the vice-president of the national chapter of the NGO Transparency International.
 Former deputy mayor of Porto and a public voice against corruption in Portuguese politics, he ran to the presidential elections of 2016.
 Paulo de Morais, whose campaign focused on the fight against corruption, obtained more than 100 000 votes.
Richard H. "Rick" Davis, Jr. (born 1957) is an American political consultant.
 He currently serves as a Partner and Chief Operating Officer of Pegasus Sustainable Century Merchant Bank, a private equity firm specializing in sustainable development projects.
 He is a managing partner of the business development and public affairs consulting firm Davis-Manafort, located in Alexandria, Virginia.
 He is best known for being the National Campaign Manager of John McCain's 2008 Presidential campaign (from April 25, 2007 to November 4, 2008).
 In that capacity, he oversaw the development and implementation of all campaign strategy and policy development.
 Davis also served McCain as National Campaign Manager for his 2000 Republican Presidential Primary campaign ( April 6, 1999 to March 9, 2000).
Ledyard Blair Clark (August 22, 1917 – June 6, 2000) was an American liberal journalist and political activist who played key roles both as a journalist and a political operator.
 He was general manager and vice president of CBS News from 1961 to 1964, and later became editor of "The Nation" magazine.
 He was Senator Eugene McCarthy's national campaign manager for the 1968 presidential nomination.
Great America PAC is a Super PAC that supported Donald Trump in the 2016 Presidential Election.
 It was founded in 2016 by Eric Beach, a political strategist who is a veteran of presidential campaigns.
 Beach soon brought on Ed Rollins, a long time Republican campaign consultant and strategist who served as the campaign manager for Ronald Reagan's 1984 presidential campaign.
Robert E. Mook ( ; born December 3, 1979) is an American political campaign strategist and campaign manager.
 He was the campaign manager for Hillary Clinton's 2016 presidential campaign.
Mary Beth Cahill (born December 1954) is an American political figure, who served as the campaign manager of Senator John Kerry's campaign for the Democratic nomination for President.
 She was Kerry's second campaign manager; she replaced Jim Jordan in November 2003, after Jordan was fired by Kerry.
Mindy Myers is a Democratic campaign strategist who led the Democratic Senatorial Campaign Committee's independent expenditures for the 2016 election cycle.
 She has previously served as campaign manager and chief of staff to Senator Elizabeth Warren, campaign manager for the senatorial campaigns of Sheldon Whitehouse and Richard Blumenthal, and in the Clinton White House.
 In the hotbed of political foment surrounding the 2016 American general election, she was named by Politico as one of Washington, D.C.'s 30 most powerful people, one of just 5 women on that list.
Eugene Joseph McCarthy (March 29, 1916December 10, 2005) was an American politician, poet, and a long-time Congressman from Minnesota.
 He served in the United States House of Representatives from 1949 to 1959 and the United States Senate from 1959 to 1971.
 McCarthy sought the Democratic nomination in the 1968 presidential election, challenging incumbent Lyndon B. Johnson on an anti-Vietnam War platform.
 McCarthy would unsuccessfully seek the presidency five times altogether.