Question: What county is the city named Clayton in where residents could vote for Tom Harkin?

full_context: Document 1: John Kerry: Meanwhile, Kerry's staff began their own investigations and, on October 14, issued a report that exposed illegal activities on the part of Lieutenant Colonel Oliver North, who had set up a private network involving the National Security Council and the CIA to deliver military equipment to right-wing Nicaraguan rebels (Contras). In effect, North and certain members of the President's administration were accused by Kerry's report of illegally funding and supplying armed militants without the authorization of Congress. Kerry's staff investigation, based on a year-long inquiry and interviews with fifty unnamed sources, is said to raise "serious questions about whether the United States has abided by the law in its handling of the contras over the past three years."
Document 2: John Kerry: On April 18, 1985, a few months after taking his Senate seat, Kerry and Senator Tom Harkin of Iowa traveled to Nicaragua and met the country's president, Daniel Ortega. Though Ortega had won internationally certified elections, the trip was criticized because Ortega and his leftist Sandinista government had strong ties to Cuba and the USSR and were accused of human rights abuses. The Sandinista government was opposed by the right-wing CIA-backed rebels known as the Contras. While in Nicaragua, Kerry and Harkin talked to people on both sides of the conflict. Through the senators, Ortega offered a cease-fire agreement in exchange for the U.S. dropping support of the Contras. The offer was denounced by the Reagan administration as a "propaganda initiative" designed to influence a House vote on a $14 million Contra aid package, but Kerry said "I am willing..... to take the risk in the effort to put to test the good faith of the Sandinistas." The House voted down the Contra aid, but Ortega flew to Moscow to accept a $200 million loan the next day, which in part prompted the House to pass a larger $27 million aid package six weeks later.
Document 3: Dow City, Iowa: Dow City is a city in Crawford County, Iowa, United States, along the Boyer River. The population was 510 at the 2010 census.
Document 4: Everly, Iowa: Everly is a city in Clay County, Iowa, United States. The population was 603 in the 2010 census, a decline from 647 in the 2000 census. The Ocheyedan River flows to the south and west of the city.
Document 5: Clayton Township, Perry County, Ohio: Clayton Township is one of the fourteen townships of Perry County, Ohio, United States. The 2000 census found 1,432 people in the township.
Document 6: Clayton Township, Adams County, Illinois: Clayton Township is one of twenty-two townships in Adams County, Illinois, United States. As of the 2010 census, its population was 1,027 and it contained 465 housing units.
Document 7: John Kerry: The Kerry Committee report found that "the Contra drug links included..... payments to drug traffickers by the U.S. State Department of funds authorized by the Congress for humanitarian assistance to the Contras, in some cases after the traffickers had been indicted by federal law enforcement agencies on drug charges, in others while traffickers were under active investigation by these same agencies." The U.S. State Department paid over $806,000 to known drug traffickers to carry humanitarian assistance to the Contras. Kerry's findings provoked little reaction in the media and official Washington.
Document 8: John Kerry: During their investigation of Noriega, Kerry's staff found reason to believe that the Pakistan-based Bank of Credit and Commerce International (BCCI) had facilitated Noriega's drug trafficking and money laundering. This led to a separate inquiry into BCCI, and as a result, banking regulators shut down BCCI in 1991. In December 1992, Kerry and Senator Hank Brown, a Republican from Colorado, released The BCCI Affair, a report on the BCCI scandal. The report showed that the bank was crooked and was working with terrorists, including Abu Nidal. It blasted the Department of Justice, the Department of the Treasury, the Customs Service, the Federal Reserve Bank, as well as influential lobbyists and the CIA.
Document 9: John Kerry: During his bid to be elected president in 2004, Kerry frequently criticized President George W. Bush for the Iraq War. While Kerry had initially voted in support of authorizing President Bush to use force in dealing with Saddam Hussein, he voted against an $87 billion supplemental appropriations bill to pay for the subsequent war. His statement on March 16, 2004, "I actually did vote for the $87 billion before I voted against it," helped the Bush campaign to paint him as a flip-flopper and has been cited as contributing to Kerry's defeat.
Document 10: Clayton, Iowa: Clayton is a city in Clayton County, Iowa, United States. The population was 43 at the 2010 census, down from 55 at the 2000 census. Clayton is located directly on the Mississippi River and is only accessible by a very steep road. Many people have summer homes in Clayton due to its proximity to the Mississippi River.
Document 11: Clayton, Missouri: Clayton is a city in and the county seat of St. Louis County, Missouri, United States, and borders the city of St. Louis. The population was 15,939 at the 2010 census. The city was organized in 1877 and is named after Ralph Clayton, who donated the land for the courthouse. The city is known for its multiple skyscrapers in its business district.
Document 12: Nicaraguan Revolution: The Nicaraguan Revolution (Spanish: Revolución Nicaragüense or Revolución Popular Sandinista) encompassed the rising opposition to the Somoza dictatorship in the 1960s and 1970s, the campaign led by the Sandinista National Liberation Front (FSLN) to violently oust the dictatorship in 1978 -- 79, the subsequent efforts of the FSLN to govern Nicaragua from 1979 until 1990 and the Contra War which was waged between the FSLN - led government of Nicaragua and the United States - backed Contras from 1981 - 1990.
Document 13: Summit Township, Clay County, Iowa: Summit Township is a township in Clay County, Iowa, USA. As of the 2000 census, its population was 452. Spencer Municipal Airport is located in the township.
Document 14: John Kerry: After receiving his J.D. from Boston College Law School, Kerry worked in Massachusetts as an Assistant District Attorney. He served as Lieutenant Governor of Massachusetts under Michael Dukakis from 1983 to 1985 and was elected to the U.S. Senate in 1984 and was sworn in the following January. On the Senate Foreign Relations Committee, he led a series of hearings from 1987 to 1989 which were a precursor to the Iran–Contra affair. Kerry was re-elected to additional terms in 1990, 1996, 2002 and 2008. In 2002, Kerry voted to authorize the President "to use force, if necessary, to disarm Saddam Hussein", but warned that the administration should exhaust its diplomatic avenues before launching war.
Document 15: Clay City Township, Clay County, Illinois: Clay City Township is one of twelve townships in Clay County, Illinois, USA. As of the 2010 census, its population was 1,287 and it contained 649 housing units.
ground_truth: Clayton County
sub_queries: Where was Tom Harkin from? Answer: Iowa
Clayton, Iowa >> located in the administrative territorial entity Answer: Clayton County