For most of the time from 1903 to 2005, the 10th was centered on Austin. It originally included large portions of the Texas Hill Country. Future PresidentLyndon B. Johnson represented this district from 1937 to 1949. During the second half of the 20th century, Austin's dramatic growth resulted in the district becoming more compact over the years. By the 1990s, it was reduced to little more than Austin itself and surrounding suburbs in Travis County.
However, in a mid-decade redistricting conducted in 2003, the 10th was dramatically altered. It lost much of the southern portion of its territory. To make up for the loss in population, it was extended all the way to the outer fringes of Houston, making the new district heavily Republican. Five-term Democratic incumbent Lloyd Doggett was forced to transfer to another district. McCaul won the open seat in 2004, and has held it ever since.
Due to the 2003 mid-decade redistricting plan, the 10th's boundaries were gerrymandered forcing Democratic incumbent Lloyd Doggett to redistrict to the 25th district. Attorney Michael McCaul won the Republican nomination and ran without any major-party opposition.
Incumbent Michael McCaul faced Assistant Attorney of Austin Mike Siegel in the 2018 general election, winning by 4.3 percent of the vote. This is the closest contest McCaul has faced.[9] The outcome was notable in a district that political experts rated as "Heavily Republican."[10][11]