Question: What U.S. senator held office from 2001 to 2009 and won by a two-to-one margin in their reelection? 

Context paragraphs:
Carol Moseley Braun: Carol Elizabeth Moseley Braun, also sometimes Moseley-Braun (born August 16, 1947), is an American diplomat, politician and lawyer who represented Illinois in the United States Senate from 1993 to 1999.  She was the first female African-American Senator, the first African-American U.S. Senator for the Democratic Party, the first woman to defeat an incumbent U.S. Senator in an election, and the first female Senator from Illinois.  She was the only female U.S. Senator from Illinois until Tammy Duckworth who became the U.S. Senator from Illinois in January 2017.  From 1999 until 2001, she was the United States Ambassador to New Zealand.  She was a candidate for the Democratic nomination during the 2004 U.S. presidential election.  Following the public announcement by Richard M. Daley that he would not seek re-election, in November 2010, Braun began her campaign for Mayor of Chicago.  The former Senator placed fourth in a field of six candidates, losing the February 22, 2011, election to Rahm Emanuel.

Pennsylvania's 10th congressional district: Pennsylvania's 10th Congressional District is located in the central and northeast regions of the state.  The district was one of the 12 original districts created prior to the 4th Congress.  It is currently represented by Republican Tom Marino, who defeated Democratic incumbent Chris Carney during the 2010 U.S. House elections.  In 2006, the 10th district experienced one of the greatest party shifts among all House seats that switched party control: in 2004, Republican Don Sherwood won with an 86% margin of victory over his nearest opponent and two years later, Carney unseated Sherwood by a 53%–47% margin.  In 2008, Carney won reelection by 12 points but the district swung back in 2010, electing Tom Marino.  The district is mostly Republican in its political composition, an aspect of the district that is reflected especially well in presidential elections.  In 2004, President George W. Bush won 60 percent of the vote in the district and in 2008, Senator John McCain beat Senator Barack Obama here by a margin of 54 percent to 45 percent.  Nonetheless, Carney easily won reelection as a Democrat the same year McCain won the district.  However, in the 2010 midterm elections, Marino unseated Carney by a 55%–45% margin.  In 2016, local business man and former mayor of Lewisburg, Pennsylvania, Mike Molesevich challenged Marino for the seat, but he fell to the Republican in November by more than two to one.  Marino remains the congressman in the 10th district, but he has expressed interest in a 2018 gubernatorial run rather than standing for reelection.

Nebraska Democratic caucuses, 2008: The Nebraska Democratic Presidential Caucuses took place on February 9, 2008, where 24 of the state's 31 convention delegates were chosen.  Like he did throughout many other states that held caucuses instead of primaries, Barack Obama won the Nebraska Democratic Caucus by more than a two-to-one margin of victory over Hillary Clinton.  On May 13, 2008, the state also held a non-binding primary election which Obama also won but the margin of victory was considerably smaller.

United States Senate election in Arizona, 1958: The 1958 United States Senate elections in Arizona took place on November 4, 1958.  Incumbent Republican U.S. Senator Barry Goldwater ran for reelection to a second term, and defeated former U.S. Senator, and then-Governor, Ernest McFarland in the general election.  The election was a virtual rematch from 1952, where Goldwater defeated McFarland by a narrow margin.  Goldwater had attributed the win to the unpopularity of President Harry S. Truman and popular Wisconsin Senator Joseph McCarthy endorsing his campaign.

United States Senate election in New York, 2006: The 2006 United States Senate election in New York was held November 7, 2006.  Incumbent Democratic U.S. Senator Hillary Rodham Clinton won, by a more than two-to-one margin, a second term representing New York in the United States Senate.  Clinton was challenged by Republican John Spencer, a former Mayor of Yonkers, New York.  Spencer won his party nomination by defeating former national security staffer K. T. McFarland in a primary.

United States Senate career of Hillary Clinton: Hillary Rodham Clinton served as a United States Senator from New York from January 3, 2001 to January 21, 2009.  She won the United States Senate election in New York, 2000 and the United States Senate election in New York, 2006.  Clinton resigned from the Senate on January 21, 2009 to become United States Secretary of State for the Obama Administration.

United States Senate election in Arizona, 1980: The 1980 United States Senate election in Arizona took place on November 4, 1980.  Incumbent Republican U.S. Senator Barry Goldwater decided to run for reelection to a third consecutive term, after returning to the U.S. Senate in 1968 following his failed Presidential run in 1964 against Lyndon B. Johnson.  Goldwater defeated Democratic Party nominee Bill Schulz in the general election, but only by a narrow margin, which later caused Goldwater to decide against running for reelection to a fourth consecutive term.

Colorado Democratic caucuses, 2008: The Colorado Democratic Presidential Caucus took place on Super Tuesday, February 5, 2008.  As he did in every other state that held a caucus rather than a primary, Barack Obama won the caucus by a wide, two-to-one margin over Hillary Clinton.

United States Senate election in Arizona, 1968: The 1968 United States Senate election in Arizona took place on November 5, 1968.  Incumbent Democratic U.S. Senator Carl Hayden did not run for reelection to an eighth term, with his longtime staff member Roy Elson running as the Democratic Party nominee to replace him.  Elson was defeated by a wide margin, however, by former U.S. Senator and Republican Presidential nominee Barry Goldwater.  Prior to Goldwater's election, the seat had been held for decades by the Democratic Party under Carl Hayden, and has thus far remained in Republican Party control since.

Slade Gorton: Thomas Slade Gorton III (born January 8, 1928) is an American politician.  A Republican, he was a U.S. Senator from Washington state from 1981 to 1987, and from 1989 to 2001.  He held both of the state's Senate seats in his career and was narrowly defeated for reelection twice as an incumbent: in 1986 by Brock Adams, and in 2000 by Maria Cantwell after a recount.  Gorton was twice both senior senator (1983–87, 1993–2001) and junior senator (1981–83, 1989–93).  Since Gorton's 2000 re-election loss, no other Republican from Washington has been elected as a U.S. Senator.

Supporting paragraphs: United States Senate career of Hillary Clinton United States Senate election in New York, 2006
Answer: Hillary Rodham Clinton