With support for Texas republican Senator John Cornyn hovering around 50 percent or less in polls, Democrats believe he's vulnerable.

Cornyn is up for re-election.

Despite his weaker-than-expected showing, Democratic nominee Rick Noriega still calls it a David-versus-Goliath battle.

But Noriega thinks he has a chance, and says that as a senator, he would put Texas first.

"Mr. Cornyn has had now for six years, with all the cards stacked in his favor, the opportunity to lead, and he has failed the families of the state of Texas," Noriega said.

Noriega has served as a state representative from Houston since 1999.

He's a Lieutenant Colonel in the Army National Guard and works as a manager at CenterPoint Energy.

Noriega criticizes incumbent Republican John Cornyn for supporting the war in Iraq and not doing more to lower energy costs.

"The people of the State of Texas deserve a credible and viable alternative to the status quo that has supported 97 per cent of the time the failed policies of this administration," he said.

The take on Noriega by opponent Cornyn: "He's not in sync with the typical Texas values."

Cornyn holds a huge fundraising advantage, which will become clear after Labor Day, when he starts a TV ad campaign Noriega can't afford.

For Noriega to have a chance, he must look to enthusiastic Democrats turning out for Obama and unhappy independents and Republicans.

"If elections were purely determined based on the money, then what's the point of having elections?" he asked.

E-mail bwatson@wfaa.com.