HOUSTON -

Texas Democrats opened their convention Thursday with leaders promising to continue building on local successes to make the party more competitive in the Republican-dominated state.

Party Chairman Boyd Ritchie told a state executive committee meeting that the party's successes in local elections in Dallas and Houston laid the groundwork for bigger wins.

"We saw major metro areas turn blue, we've won congressional districts that most thought were unwinnable, we prevailed in countless county races," Ritchie told the committee. "When we prevail, it will be on the foundation that you all built."

Republicans hold every statewide office and majorities in both chambers of the Legislature. But a growing Hispanic population and new political districts give Democrats a chance to chip at the Republican 12-48 supermajority in the Texas House. Ritchie acknowledged that the party has work to do, but said new Democratic leaders were emerging.

San Antonio Mayor Julian Castro will give the keynote address and U.S. Trade Representative Ron Kirk, a former Dallas mayor, will give a major speech Friday. Democrats also will feature Dallas County Judge Clay Jenkins as someone to watch in the party, Ritchie said.

Democrats will spend much of their time in Houston holding caucus, district meetings and workshops on fundraising and social media. No Democrat has won a statewide office since 1994, and Republicans hold a 102-48 supermajority in the Texas House. But redistricting is expected to bring that number down in November, and Ritchie feels Democrats could make additional gains.

"It seems to me that a lot of the extreme rightwing positions that a lot of the Republicans took to get out of their primaries will ultimately be responsible for us having an opportunity to win in November," Ritchie told The Associated Press before the convention.

Ritchie also wants to motivate Democrats to vote in runoff primary elections set for July 31. The only statewide race pits former state Rep. Paul Sadler against retired educator Grady Yarbrough for the U.S. Senate nomination. Yarbrough did not mount a campaign, and Sadler will speak to the convention Friday night.

Ritchie said the fact that Yarbrough made it into the runoff was proof that having a well-known name influences voters. Yarbrough's name is reminiscent of one of the Texas Democrat's greatest progressive heroes, Ralph Yarborough, who served in the U.S. Senate in the 1960s.

"Lots and lots of voters, I am satisfied, thought that this somehow was either a relative or the former senator," Ritchie said. "The problem is that Mr. Yarbrough has run for office before, for statewide office, as a Republican. There are some people who decide to run for the heck of it."

So far Democratic donors have given Sadler, the front-runner, less than $100,000 for the Democratic primary race and he will seek to rally support for his runoff and a possible race against the winner of the Republican runoff, either Lt. Gov. David Dewhurst or former Texas Solicitor General Ted Cruz. Combined they spent more than $20 million on their primary race.

"We're not ever going to be able to play on a level field as far as money is concerned," Ritchie admitted. "People I think are disgusted with that, and hopefully they can understand that it all came about from extreme right-wing positions."

The Texas Republican Convention is also being held this week in Fort Worth.

The Democratic National Convention will be held in Charlotte, N.C., Sept. 3 to 6. The Republican National Convention will be held in Tampa, Fla., Aug. 27 to 30.