"We're just tired of the government ignoring the Constitution," Steinway said. "I'm tired of these people who promise something for nothing."
Texas Democratic Party Chairman Gilberto Hinojosa called the win "the worst thing that could have happened to Texas Republicans."
"It's a tea-flavored mutiny, plain and simple," he said.
Democrats, who haven't won a statewide election in Texas since 1994, picked Sadler, from Henderson in East Texas, over retired San Antonio educator Grady Yarbrough as their choice for U.S. Senate.
Neither raised much money and Yarbrough failed to comply with federal election laws concerning where he had raised money or how he has spent it, according to the Federal Election Commission.
In all, there were 25 Republican and 12 Democratic runoffs, including two Railroad Commission races, one Supreme Court race, three State Board of Education races, eight U.S. House and 17 Texas Legislature races.
Among them were fierce Democratic congressional races in Dallas-Fort Worth and San Antonio.
State Rep. Marc Veasey of Fort Worth had a narrow lead in early votes over longtime Hispanic activist and former state Rep. Domingo Garcia for a new congressional district in the Metroplex, one of four new Texas districts thanks to the state's booming population. Veasey turned out African-American voters in Fort Worth in the May 29 primary and Garcia tried to mobilize his base in Dallas.
In San Antonio, former U.S. Rep. Ciro Rodriguez looked for a chance to regain his seat from Republican Quico Canseco, and was locked in a tight race with state Rep. Pete Gallego, a rising star in the Democratic Party.
Republicans had similar congressional battles.
Roger Williams, a close ally of Gov. Perry, beat tea party-favorite Wes Riddle in an Austin-area district. Along the Gulf Coast, state Rep. Randy Weber of Pearland defeated Felicia Harris, a Republican party activist, to secure the GOP nomination in the district now represented by retiring Ron Paul. Weber will face former Democratic Rep. Nick Lampson in November.
In far Southeast Texas, financial planner Stephen Takach tried to keep former one-term congressman Steve Stockman from securing the GOP nomination in another new district. The results remained close.
The outcomes of Texas House and Senate runoffs could make the Legislature a more tumultuous place.
Veteran Republican Sen. Jeff Wentworth of San Antonio lost in his tough runoff campaign against emergency room physician Donna Campbell, a tea party leader making her second bid for office.
In state House races, senior committee chairmen Rep. Sid Miller of Stephenville and Rep. Chuck Hopson of Jacksonville were defeated in anti-incumbent, tea party insurgencies. Miller lost to family doctor J.D. Sheffield, of Gatesville. Hopson, a former Democrat, lost to Travis Clardy, an attorney from Nacogdoches.