John Harris Whitmire (born August 13, 1949) is the longest-serving of current members of the Texas State Senate representing District 15, which includes much of northern Houston, since 1983. Previously he was a member of the Texas House of Representatives from 1973 through 1982. He also served as the Acting Governor of Texas in 1993 as part of the Governor for A Day tradition.
Whitmire was born in Hillsboro, Texas to James M. Whitmire and Marie Harris Whitmire and graduated from Waltrip High School and the University of Houston.
In 2003, Whitmire was one of the "Texas Eleven", a group of Democrats who fled the state for New Mexico in 2003 in a quorum-busting effort aimed at preventing the passage of controversial redistricting legislation that would have benefited Texas Republicans.