Texas Attorney General Greg Abbott, a fierce social conservative, formally kicked off his 2014 campaign for governor.
It was a long-expected move, as Abbott had in previous campaigns mulled running but many political observers said he was not sure about taking on popular Rick Perry.
In a rally held Sunday in San Antonio, he said he wants to succeed Gov. Rick Perry, who announced last week he won't seek a fourth term.
Abbott has already raised nearly $23 million.
Abbott has held office since 2002 and is popular among mainstream Republicans and tea party activists. Abbott has also sued the federal government on Texas' behalf 27 times during the Obama administration.
The only other announced candidate from either party is ex-state Republican Party chairman Tom Pauken.
No Democratic candidate has emerged, though some have urged state Sen. Wendy Davis to run. She gained notoriety for her 12-plus-hour filibuster over sweeping new abortion limits during the Legislature's first special session.
Making the announcement in San Antonio puts Abbott in a predominately Hispanic city at a time when Battleground Texas, a group led by former staffers from President Barack Obama's successful re-election campaign, is trying to turn Texas Democratic — given the state's surging Hispanic population.
The Lone Star State is home to the second largest Latino population in the United States. About 9.5 million Hispanics reside in Texas, according to the Pew Hispanic Center. They make up nearly 40 percent of the state's population.
San Antonio Mayor Julian Castro spoke at the Democratic National Convention last year and has often been mentioned as a future gubernatorial candidate, though he hasn't confirmed any future plans.
Last week his official Twitter account retweeted a message about a new nationwide poll of Latino likely voters showed that 62 percent of respondents would more likely vote Democrat if Castro were the vice presidential candidate in 2016.
Perry's bowing out means at least six out of Texas' nine elected executive offices will change hands. Voters will replace the governor, attorney general, comptroller and commissioners for land, agriculture and railroads.
They'll also get a chance to choose another lieutenant governor, with three top Republicans running to replace David Dewhurst — even though he plans to seek re-election.
Based on reporting by The Associated Press.