Incumbent Republican U.S. senator Kay Bailey Hutchison decided to retire instead of running for reelection to a fourth full term.

[6] On January 15, 2009, Hutchison transferred nearly all the money, approximately $8 million, from her federal campaign account to her gubernatorial exploratory committee.

The Texas Libertarian Party nominated John Jay Myers as its Senate candidate, using approval voting on June 9 at the state convention in Fort Worth.

The Green Party of Texas reported two candidates pre-selected at the June 9 convention:[110] David B. Collins and Victoria Ann Zabaras.

[117] [118] with David Dewhurst with Julian Castro with Chet Edwards with Sean Hubbard with Tommy Lee Jones with Paul Sadler with Ricardo Sanchez with John Sharp with Bill White Republican primary (when asked specifically, if Dewhurst were not running) Cruz won 25 of 36 congressional districts, including one that elected a Democrat.