Theodore Gatsas (born May 22, 1950) is an American politician and member of the Republican party who had served as Mayor of Manchester, New Hampshire from 2010 to 2018.
He was a member of the New Hampshire Senate, representing the 16th District from 2000 until he resigned in 2009 after being elected mayor.Gatsas was educated at Manchester Central High School.
He graduated from the University of New Hampshire at Manchester with a Bachelor of Science degree.
He then started Staffing Network, a PEO, with his brother Michael.
Gatsas was elected alderman in the Manchester city council in 1999, and later elected to the New Hampshire Senate in 2000.
He became President of the Senate in 2005 by cutting a deal mid-term with the minority Democrats to remove two-term Republican Senate President Tom Eaton.
He was elected Senate Minority Leader after the Democrats took control of the State Senate in 2006.
Gatsas is Greek American.
The Greek Orthodox Church Metropolitan of Boston, Metropolitan Methodios, gave the invocation at his 2015 inauguration.