HALTOM CITY, Texas (Reuters) - Wendy Davis, the Texas state senator who staged a filibuster against sweeping abortion restrictions, announced on Thursday that she would run for governor of the state.

"Texas is a place where we aim high and we take big risks," Davis told hundreds of cheering supporters at a rally outside Fort Worth. "We're builders, and doers, leaders, and dreamers. We love Texas, not only for how good it is, but for how great we know it can be."

The announcement ends months of speculation over the political future of the 50-year-old Democrat, who gained national attention when she talked for nearly 11 hours on the Texas Senate floor in June to temporarily block new restrictions on abortion.

Davis, a second-term state senator, saw her popularity skyrocket when her stand in the now-famous pink running shoes drew thousands of demonstrators to the state capitol and played out in livestreams on websites across the United States.

The bill would have banned most abortions after 20 weeks and imposed strict new requirements on clinics. It eventually passed, but Davis' newfound popularity continued and she was able to add $1 million to her campaign coffer.

Davis, who unseated a Republican incumbent to win her Senate election, seeks the spot held by Republican Gov. Rick Perry, the former presidential contender who has said he will not seek re-election.

Davis emphasized education and healthcare during her announcement at a rally on Thursday afternoon at the coliseum where she received her high school diploma, in the working-class Fort Worth suburb of Haltom City. About two dozen anti-abortion protesters carried signs outside the coliseum during the event.

Davis took the stage as the Alicia Keys song, "This Girl is on Fire," blared over loudspeakers.

A Harvard graduate and twice-divorced mother of two, Davis rose from poverty as a single teen mom in a Texas trailer park to a successful career in law and politics.

"No matter where you start, no matter how you start, that place has nothing to do with how far you can go," Davis said on Thursday. "God bless you all. God bless Texas."

If Davis gets her party's nod during the primaries next spring, she is expected to face an uphill battle.

Her likely opponent would be Texas Attorney General Greg Abbott, the current GOP frontrunner who has amassed a war chest close to $25 million. The election is due to be held in November 2014.

Perry has not said what his plans are, but many speculate that he will try a second time for the Republican nomination for president. His attempt in 2011 fell flat.

Supporters of Davis in Texas had been trying to recruit her to run for governor since 2011, when she forced Republicans into a special legislative session over their plans to cut billions from state education, another bill that eventually passed the GOP-dominated statehouse.

Her filibuster earlier this summer, which landed her on the cover of the September issue of Vogue magazine, identified her as the Democrat who might have the best chance of claiming the state's top seat after nearly 20 years of Republican victories in statewide races.

The last Democrat to win the governor's spot was Ann Richards in 1990. Republicans have won every statewide seat since 1994 and have dominated the Texas Legislature since 2003.

Davis' rags-to-riches-to-politics story has been one of her strongest political allies.

Born in Maryland, Davis moved with her family to North Texas as a child, but her parents divorced and her father left to work in community theater.

Davis began working at age 14 to help support her mother and three siblings, according to her official biography.

After graduating from high school in 1981, Davis became pregnant, married her boyfriend and gave birth to daughter Amber in 1982, records show.

By age 19, the marriage had broken up and Davis was a single mother working two jobs and living in a trailer she and her ex-husband had bought.

Davis spent two years in a community college paralegal program before getting her bachelor's degree at Texas Christian University with the help of scholarships and loans.

In 1987, she married Jeff Davis, a lawyer and former Fort Worth city councilman, and had a daughter, Dru. With her husband's support, she graduated Harvard Law School with honors.

Davis became a practicing attorney in Fort Worth and served nine years on the Fort Worth City Council. The couple divorced in 2005, according to court records, and her ex-husband retained custody of their daughter, 17, while Davis paid $1,200 a month in child support.

(Editing by Karen Brooks, Diane Craft and David Gregorio)