Valesky was first elected to the State Senate in 2004 when he defeated longtime incumbent Sen.
Nancy Larraine Hoffmann (R-Fabius). Hoffman was challenged in a Republican primary by Tom Dadey. While Hoffmann defeated Dadey, Dadey remained in the race on third-party lines. Valesky prevailed in the three-way race. He took office as a state senator in January 2005. In 2011, Valesky joined with
Jeffrey D. Klein,
Diane Savino, and
David Carlucci to form the
Independent Democratic Conference (IDC). On April 16, 2018, the IDC was dissolved and Valesky returned to the Senate Democratic Conference. In the 2018 Democratic primary, Valesky was defeated by
Rachel May. Valesky received 46.66% of the primary vote to May's 50.47%. All eight former members of the IDC faced progressive primary challenges in 2018, and six were defeated. ==References==