Sean Casten

On November 6, 2018, Casten won the election, defeating Roskam by a margin of 7 points. Casten ran on a platform focused on climate change mitigation and political transparency; before his win, he said that his legislative goals in response to his district's main needs were to support health care access (criticizing Roskam's votes against the Affordable Care Act and against individual mandates), to work against the tax bill Roskam sponsored, and to reform student loan and bankruptcy codes.

Casten announced his candidacy for the United States House of Representatives in Illinois's 6th congressional district in September 2017. He defeated six other contenders in the 2018 Democratic primary to become the party's nominee against six-term incumbent Republican Peter Roskam.

Casten was a founding chairman of the Northeast CHP Initiative, a nonprofit advocacy organization with a mission to advance policies that favor energy efficiency in the northeast United States. He also participated in crafting the bill that became the Regional Greenhouse Gas Initiative (RGGI), a program in the northeast United States that attempts to use market forces to reduce greenhouse gas emissions. For his advocacy of clean energy policies and technology, Casten was named to the Chicago Council on Global Affairs' Emerging Leaders Class of 2011.

This race was viewed as one that Democrats needed to win in order to regain control of the U.S. House of Representatives for the first time since the 2010 elections. Illinois's 6th congressional district supported Democratic presidential nominee Hillary Clinton by about 7 percentage points in the 2016 presidential election. This was one of 25 GOP-held seats in the U.S. Representatives that Clinton carried in 2016; Democrats flipped 23 of them in 2018.

In 2006, Casten founded Recycled Energy Development (RED) and served as CEO along with his father Tom Casten, who served as Chairman. Casten moved to Illinois in 2007. RED focused on recycling wasted energy and converting energy facilities to cleaner, more economic uses. RED was a leading company in the United States in the attempt to make profitable use of waste heat capturing technology, an avenue of electricity generation that has been attracting interest from a number of startup companies looking to find a "breakthrough" in the technology, including Alphabet. The company was acquired by Ironclad Energy Partners in 2016.

Casten began his career working as a clean energy consultant and manager at Arthur D Little, an energy practice with a focus on clean technology. From 2000 to 2006, he served as the president and CEO of Turbosteam Corporation, which focused on utilizing energy recycling technologies to reduce greenhouse gas emission by generating heat and power from previously wasted energy.

Born in Dublin, Ireland,, and raised in Hartsdale, NY, Casten earned a bachelor of arts in molecular biology and biochemistry from Middlebury College in 1993, and then worked for two years as a scientist at the Tufts University School of Medicine in a laboratory investigating dietary impacts on colon and breast cancer. In 1998, he earned a Master of Engineering Management and a Master of Science in biochemical engineering from the Thayer School of Engineering at Dartmouth College. While at Dartmouth, he worked to develop technologies for alternative heat and power generation technologies including the production of fuel grade ethanol. Casten is a member of Thayer School of Engineering’s Corporate Collaboration Council.

Sean Thomas Casten (born November 23, 1971) is an American entrepreneur and Democratic politician serving as the U.S. Representative for Illinois's 6th congressional district . The district covers portions of five counties, and includes many of Chicago's western suburbs, such as Wheaton, Palatine, and Barrington.

Upon his swearing-in, Casten became the first Democrat to represent this district since it assumed its present configuration in 1949. The district had been numbered as the 10th from 1949 to 1967, and has been the 6th since 1967. The district is best known as the seat of former House Judiciary Committee chairman Henry Hyde, who held it from 1973 until handing it to Roskam upon his retirement in 2007.