"All of you deserve to have your voices heard. Because our future is brightest when it's lit by everyone's star," Davis said Thursday in her announcement speech. "That's why today, I am proud to announce my candidacy to be the 48th governor of this great state."
Davis' filibuster delayed the abortion bill, but did not kill it.
On Thursday, she spoke out against Republican Gov. Rick Perry, who supported the measure.
"In Austin today, our current leadership thinks that promises are just something you make to the people who write you big checks," Davis said. "But the ... promise that I'm talking about is bigger than that. It's the promise of a better tomorrow for everyone."
Davis faces a tough challenge in a state that has had Republican governors since the mid-1990s, CNN said.
Her most likely opponent is Republican Texas Attorney General Greg Abbott, CNN said.