Stephan Joseph "Steve" Kornacki, Jr. (born August 22, 1979) is an American political journalist, writer, and television host. Kornacki is National Political Correspondent for NBC News and is known for his work as contributor and co-host of the 4 P.M. edition of MSNBC Live. Kornacki has written articles for Salon, The New York Observer, The Wall Street Journal, The New York Times, the New York Daily News, the New York Post, The Boston Globe, and The Daily Beast. Kornacki was the multimedia anchor and data analyst for much of MSNBC's The Place for Politics campaign coverage, airing throughout 2016.
Stephan Joseph Kornacki, known as Stevie as a youngster, was born in Groton, Massachusetts, to parents of Polish and Lithuanian descent, Stephan Joseph Kornacki, Sr., and Anne Ramonas. He has an older sister, Kathryn "Katie" Kornacki, who graduated from University of Connecticut, and is currently a professor at Caldwell University. 
Kornacki started his journalism career as a reporter for PoliticsNJ.com, a New Jersey political news site owned by David Wildstein, where he worked from 2002-06. He formerly co-hosted a political news series at News 12 New Jersey and reported on the U.S. Congress for the newspaper Roll Call. His articles have been published in the New York Observer, The Wall Street Journal, The New York Times, the New York Daily News, the New York Post, The Boston Globe, and The Daily Beast. He joined the writing staff of Salon.com in 2010.
He co-hosted The Cycle on MSNBC with political strategist Krystal Ball, pop-culture commentator Touré Neblett, and conservative columnist S.E. Cupp from the program's inception through March 20, 2013. On March 19, 2013, it was announced that Kornacki would take over another MSNBC program, Up, airing Saturdays and Sundays from 8 to 10 a.m., starting in April. Beginning in 2016, Kornacki hosted a daily program from 4 p.m. to 5 p.m., and frequently guest hosts on Hardball with Chris Matthews, All In with Chris Hayes and The Rachel Maddow Show.
In May 2017, Kornacki transitioned away from anchor duties at MSNBC and toward more franchise reporting for NBC News. On May 8, 2017, Kornacki was named National Political Correspondent for NBC News Group, with plans to continue co-hosting the 4 p.m. edition of MSNBC Live with Nicolle Wallace.