I'd like to sell my house through a raffle. Is that legal?

This page from the Texas Attorney General's website explains who is qualified to hold a raffle in Texas. Regarding raffles not authorized by law, they state the following:

An unauthorized raffle is considered gambling under the Texas Penal Code. Conducting such a raffle is a Class A misdemeanor. Participating in an unauthorized raffle is a Class C misdemeanor.

The Attorney General's website refers you to the Charitable Raffle Enabling Act (Occupations Code chapter 2002) for the text of the laws on authorized raffles. In addition, you may want to review Texas Penal Code chapter 47 on gambling and the Contest and Gift Giveaway Act.