Jonathan Bartlett Jennings (born March 27, 1974) is an American politician and farmer who has served as a member of the Maryland Senate representing the seventh district since 2011.

A member of the Republican Party, he previously represented the district in the Maryland House of Delegates from 2003 to 2011, and served as the minority leader of the Senate from 2014 to 2020.

[4][5][6] As an Airman 1st Class, he was activated for military service at Robins Air Force Base in Georgia during his first term as a state senator in 2011, causing him to miss the entire session.

[2] Jennings ran for the Maryland House of Delegates in 2002, on a platform that included issues involving school crowding and over-development.

[2] In October 2009, after state senator Andy Harris announced that he would run for Congress in Maryland's 1st congressional district in 2010, Jennings entered the race to succeed him.

[11] In the Republican primary election, he faced former Maryland Insurance Commissioner Alfred W. Redmer Jr.,[3] whom he defeated with 61 percent of the vote.

[5] During the 2020 legislative session, Jennings voted against overriding Governor Larry Hogan's veto of a bill that prevented businesses from asking job applicants about their criminal history before the first in-person interview.

[21] He also introduced a bill that would allow the governor to declare a state of emergency in Baltimore amid its high crime rates.

[22] During the 2013 legislative session, Jennings was one of five Republicans to vote for a bill to provide $1 billion toward renovations to Baltimore public schools.

[23] In March 2017, Jennings launched a filibuster against a bill to prohibit the state from using vouchers to improve struggling schools, during which he attempted to read off every page of the Every Student Succeeds Act.

[43] During the 2016 legislative session, Jennings expressed skepticism toward proposals to adopt automatic voter registration in Maryland.