Texas state Sen. Wendy Davis (D) will run for Texas governor, sources tell The Associated Press.

Davis, who became a darling of Democratic activists with a lengthy June filibuster of a law to restrict abortion in her state, has been traveling the country fundraising for a possible campaign. Her candidacy has been expected, but she is reportedly set to officially announce her campaign on Oct. 1.

Her decision to run gives Democrats a potentially competitive candidate in the conservative, but fast-changing, state.

Democrats haven't won a single statewide office in Texas in more than a decade and haven't held the governor's mansion for nearly 20 years. 

But they are hoping the state's shifting demographics can help them be competitive there sooner rather than later. 

Texas's Hispanic population has exploded, and the number of African Americans has grown in recent years as less conservative whites move in from other parts of the country.

Davis starts off the race at a serious financial disadvantage. Texas Attorney General Greg Abbott (R), the likely GOP nominee following Texas Gov. Rick Perry's (R) decision to retire, has already raised more than $20 million for the race. Texas is a prohibitively expensive state to campaign in, with some of the largest and most costly media markets in the country.

Davis is likely to get serious national fundraising support — EMILY's List, a group that backs pro-abortion rights Democratic women, has already been helping her raise her national profile, and a number of senators have stepped up to help her fundraise for the campaign.