Cornyn had 53 percent of the vote over Noriega's 45 percent with 25 percent of precincts reporting. Libertarian Yvonne Schick was a distant third.
All year Noriega, a Houston state legislator and Army National Guard officer who served in Afghanistan, blasted Cornyn's record, accusing him of saying one thing in Texas and doing another in Congress. Noriega looked to pick up support from voters who were fed up with the nation's financial mess and seeking change.
Cornyn, a first-term senator who often sided with President Bush's administration, attempted to cast himself as a commonsense Texan and an outsider to Washington who wasn't satisfied with the direction of the federal government.
The candidates clashed perhaps most fiercely over children's health insurance and the recent $700 billion bailout for financial institutions that Cornyn voted for and Noriega opposed. Noriega said the bailout didn't contain enough accountability for Wall Street; Cornyn said an elected leader has to make difficult decisions and take action and said the package included provisions to help regular Texans.
Noriega got big-name help in Texas during the final weeks of the race from Bill and Hillary Clinton, who attended campaign rallies with him.
But Cornyn always had the upper hand when it came to money and consistently polled ahead of Noriega. Beginning in September and until Election Day, Cornyn blanketed the television airwaves with ads using the millions of dollars he'd amassed for the race.
The commercials often showed him in a cowboy hat roaming around solemnly by himself in a picturesque part of rural Texas.
With far less campaign cash, Noriega had to pick his moments on TV and rely more heavily on Internet advertising and in-person appearances. Noriega described the race as a David-and-Goliath undertaking, but said he liked his chances.
In the Rio Grande Valley, Alva Rodriguez, a middle school special education teacher in the small town of Palmview near McAllen, said she didn't vote a straight-party Democratic ticket, though she voted for Noriega.
"It's not the party you're looking for -- it's the individuals," said Rodriguez, 42.
In an upper middle-class section of west El Paso, 39-year-old pharmaceuticals salesman John Crowe said he voted for Cornyn because of his views on national security.
"I feel like if we lose the White House, at least we can try to keep as many people in the party as possible, to provide balance," Crowe said.
Cornyn, 56, won election in 2002 after serving as Texas attorney general and a Texas Supreme Court justice. He defeated former Dallas Mayor Ron Kirk in his first Senate run, with 55 percent of the vote to Kirk's 43 percent.
When Noriega formally entered the race he advocated ending the war in Iraq and setting firm timetables for withdrawing American troops. Cornyn, meanwhile, said he supported Bush's plan of a troop surge in Iraq.
As the campaign went on, Noriega's message shifted from ending the Iraq war to helping average Texans who are struggling financially.
Noriega, 50, an economic development manager for CenterPoint Energy in Houston, has served in the Texas House of Representatives for a decade. When his military assignment took him to Afghanistan, his wife Melissa, now a Houston City Council member, temporarily took his place at the Legislature.
His Guard role sent him to serve along the Texas-Mexico border and led to his oversight of Hurricane Katrina evacuee shelters in Houston in 2005.
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