She lost the general election, receiving 23% of the vote and placed third behind Democrat Joseph E.
She was reelected in 2002 over State Senator Chellie Pingree (D), 58%–42%, and again in 2008 over Rep. In both elections, she carried every county in Maine.
In 2014, Collins defeated Democrat Shenna Bellows, 68.5%-31.5%, again carrying every county. C.-based nonprofit founded by Senator Richard Lugar released a bipartisan index in cooperation with Georgetown University, ranking Senator Collins the most bipartisan senator during the first session of the 115th Congress (and the only U. Senator from the Northeast ranked among the top 10 most bipartisan senators).
The bill was passed in the Senate and House in December 2001.
In November 2002, the Senate overwhelmingly approved the creation of the Department of Homeland Security while a Democratic effort to remove the bill's provisions fell short on a 52-to-47 vote that came after President Bush lobbied against the vote.
She served in this post until 1996, when she announced her candidacy for the seat in the U. Senate being vacated by her former boss, William Cohen, who retired to become United States Secretary of Defense under President Clinton.
With Cohen's public endorsement, she won a difficult four-way primary and faced Joe Brennan, her Democratic opponent from the 1994 gubernatorial election, in the general election.
The bill passed in the House and Senate in December, Collins stating afterward, "This was the most difficult bill to bring from conception to birth that I can imagine being involved with.
But that makes the victory doubly satisfying." In May 2005, Collins was one of fourteen senators (seven Democrats and seven Republicans) to forge a compromise on the Democrats' use of the judicial filibuster, thus allowing the Republican leadership to end debate without having to exercise the nuclear option.
After her bid for governor in 1994, Collins became the founding director of the Center for Family Business at Husson University. She often positions herself as a pivotal vote, thus becoming a focal point during highly watched legislation.