Question: What committee did an American politician and veterinarian, that predicted the United States Senate election in Alaska, 2008 would be competitive, serve as chairman for? 

full_context: Document 1: Patrick, Nevada: Patrick is an unincorporated community in Storey County which was the site of a historic ranch. The founder of the ranch, Patrick McCarran, arrived in Nevada in 1858 as a member of the United States Army under General Winfield Scott Hancock. In 1862 McCarran claimed 2600 acre of land that would become McCarran Ranch and the unincorporated community of Patrick. Patrick's son, Pat McCarran, became Nevada's first native born U.S. Senator and a staunch anti communist. Patrick Nevada is also the owner of four of the cattle in the ranch.
Document 2: Joe Heck: Joseph John “Joe” Heck (born October 30, 1961) is an American politician, physician, and U.S. Army Brigadier General who had served as the U.S. Representative for Nevada's 3rd congressional district from 2011 to 2017. Heck, a member of the Republican Party, is a board-certified physician and served as a Nevada State Senator from 2004-08. He ran unsuccessfully against Democrat Catherine Cortez Masto in the general election for the open Nevada United States Senate seat in 2016. In the same year, Heck made headlines by joining a long list of Republicans who opposed the GOP nominee for President, Donald Trump.
Document 3: John Edwards extramarital affair: John Edwards is a former United States Senator from North Carolina and a Democratic Party vice-presidential and presidential candidate who admitted to an extramarital affair in August 2008. The affair was initially reported in late-2007 by "The National Enquirer" (a U.S. supermarket tabloid newspaper), but was given little attention outside the tabloid press and political blogosphere. The "Enquirer" cited claims from an anonymous source that Edwards had engaged in an affair with Rielle Hunter, a filmmaker hired to work for his presidential campaign, and that Hunter had a child from the relationship. ABC News reported that Andrew Young, a member of Edwards' campaign team, stated that Edwards asked him to "Get a doctor to fake the DNA results ... and to steal a diaper from the baby so he could secretly do a DNA test to find out if this [was] indeed his child."
Document 4: United States Senate election in Nevada, 2012: The 2012 United States Senate election in Nevada was held on Tuesday, November 6, 2012, alongside 33 other elections to the United States Senate in other states, as well as elections to the United States House of Representatives, and the 2012 United States presidential election. The primary election was held June 12, 2012. Incumbent Republican U.S. Senator Dean Heller, who was recently appointed to this seat left vacant by resigning U.S. Senator John Ensign, was narrowly elected to his first full term over Congresswoman Shelley Berkley.
Document 5: Electoral history of Ted Stevens: Electoral history of Ted Stevens, Senior United States Senator from Alaska (1968-2008), Senate Minority Whip (1977-1981), Senate Majority Whip (1981-1985), President pro tempore of the United States Senate (2003-2007) and President pro tempore emeritus (2007-2008)
Document 6: List of United States Senators from Nevada: Nevada was admitted to the Union on October 31, 1864. Its current senators are Democrat Catherine Cortez Masto (Class 3) and Republican Dean Heller (Class 1).
Document 7: Catherine Cortez Masto: Catherine Marie Cortez Masto (born March 29, 1964) is an American attorney and politician who is the junior United States Senator from Nevada. She is a member of the Democratic Party. She previously served as the 32nd Attorney General of Nevada from 2007 to 2015.
Document 8: United States Senate election in Alaska, 2008: The 2008 United States Senate election in Alaska was held on November 4, 2008. Incumbent Republican U.S. Senator and former President pro tempore Ted Stevens ran for re-election to a seventh term in the United States Senate. It was one of the ten Senate races that U.S. Senator John Ensign of Nevada, the chairman of the National Republican Senatorial Committee, predicted as being most competitive. The primaries were held on Tuesday, August 26. Ted Stevens was challenged by Democratic candidate Mark Begich, the mayor of Anchorage.
Document 9: Pete Goicoechea: Peter J. "Pete" Goicoechea (born September 8, 1949) is a Republican member of the Nevada Senate. Goicoechea was born in Salt Lake City. He studied at Utah State University. He has owned a ranch since 1970 and also worked for many years for the Eureka County, Nevada road department. He served on the Eureka County Commission from 1987 to 2002 and then was elected to the Nevada State Assembly where he has served since. He has also served as a member of the Nevada State Land Use Planning Advisory Council, the Nevada Grazing Board, and he has been the Director of the Nevada Water Resource Association. He is affiliated with the Eureka Volunteer Fire Department, E Clampus Vitus, the Humboldt River Authority, and the Nevada Rural Health Center. Goicoechea is a Catholic. He and his wife Glady are the parents of two children.
Document 10: United States Senate election in Alaska, 1986: The 1986 United States Senate election in Alaska was held on November 3, 1986. Incumbent Republican United States Senator Frank Murkowski ran for a second term in the United States Senate and was primarily opposed by Alaska Pacific University President Glenn Olds. Following a highly competitive election in 1980, Murkowski faced a legitimate opponent in Glenn Olds, and the contest was fairly close. However, in the end, Murkowski was able to defeat Olds by a slightly wider margin than he won by six years prior.
Document 11: John Ensign: John Eric Ensign (born March 25, 1958) is an American veterinarian and former politician based in Las Vegas, Nevada. He was a Congressman and United States Senator from Nevada, serving in the latter seat from January 2001 until May 2011. He resigned amid a Senate Ethics Committee investigation.
Document 12: United States Senate election in Alaska, 1984: The 1984 United States Senate election in Alaska was held on November 6, 1984. Incumbent Republican Senator Ted Stevens sought re-election to a third term in the United States Senate. Owing to his popularity and the conservative bent of Alaska, Stevens did not face major opposition, and easily crushed former Alaska Attorney General John Havelock in the general election.
Document 13: United States presidential election, 2008: The United States presidential election of 2008 was the 56th quadrennial presidential election. It was held on Tuesday, November 4, 2008. Democratic Party nominees Barack Obama, a U.S. Senator from Illinois, and his running mate Joe Biden, a long-time U.S. Senator from Delaware, defeated Republican Party nominees John McCain, a long-time and current U.S. Senator from Arizona, and his running mate Sarah Palin, a Governor of Alaska. Obama became the first African American ever to be elected president of the United States, and Joe Biden became the first Roman Catholic ever elected vice president.
Document 14: United States Senate election in Alaska, 2004: The 2004 United States Senate election in Alaska took place on November 2, 2004 alongside other elections to the United States Senate in other states as well as elections to the United States House of Representatives, various state and local elections, and the presidential election of that year. Incumbent Republican U.S. Senator Lisa Murkowski of Anchorage, sought election to her first full term after being appointed to serve out the rest of her father's unexpired term when he resigned in December 2002 to become Governor of Alaska. Her main challenger was Democratic former Governor Tony Knowles, her father's predecessor as governor. Murkowski won by a slight margin.
Document 15: United States Senate election in Alaska, 2002: The 2002 United States Senate election in Alaska was held on November 5, 2002. Incumbent Republican United States Senator Ted Stevens ran for and won a sixth term in the United States Senate. He faced perennial candidate Frank Vondersaar, the Democratic nominee, journalist Jim Sykes, the Green Party nominee, and several other independent candidates in his bid for re-election. Ultimately, Stevens crushed his opponents to win what would be his last term in the Senate, allowing him to win with the largest margin of victory for any Senate election in Alaska, as well as the highest percentage of the vote in any of his elections.
ground_truth: National Republican Senatorial Committee