AUSTIN—A Democratic state lawmaker who recently served a tour of duty in Afghanistan announced his plans Monday to explore a bid for U.S. Senate, presenting his campaign as a referendum on the war in Iraq and of incumbent Sen. John Cornyn’s support of the administration.

State Rep. Rick Noriega, who filed the federal paperwork required to create an exploratory committee for a Senate run, said the nation has lost it’s “moral global compass,” and he is answering a call to “do the right thing.”

If he decides to get in the race, Noriega will be trying to unseat Republican Sen. John Cornyn, who on Monday launched Texas Victory, a political action committee, aimed at helping Republicans in the 2008 general election.

Cornyn, whose first term ends next year, is considered vulnerable by Democrats nationally. A staunch Bush ally, Cornyn intends to return for another six-year term. Noriega joins two other Democratic contenders. San Antonio lawyer Mikal Watts established an exploratory committee in early June, and Dallas lawyer Emil Reichstadt also has said he plans to run, but has not filed any paperwork.

Watts echoed Noriega’s criticisms of Cornyn.

“John Cornyn is the chief-apologist for the Bush Administration and their failed policies from immigration to health care to the war in Iraq,” he said.

Amid an increasing call to change course in Iraq, Cornyn said last week that he and many others would stick behind Bush. He downplayed the criticisms Monday.

“There’s going to be a primary in the Democratic party in March 2008. They’re going to choose their candidate and I’m happy to let them campaign while I do the work of the people of Texas in the United States Senate,” Cornyn said.

Watts has stated he would spend $3.8 million in the primary and pledged $6.2 million for the general election, should he win the nomination. So far, Cornyn leads in the money race. He reported raising $2.1 million for his campaign in the three months that ended June 30 and finishing the second quarter with $5.4 million in the bank.

Watts reported raising $1.14 million in June to add to the personal money he put into his campaign. He reported he has $4.9 million cash on hand.

Noriega, a lieutenant colonel in the Texas Army National Guard, spent 14 months of duty in Afghanistan and was later recalled to active duty for Hurricane Katrina. When Hurricane Rita hit Noriega was sent to help set up shelters.

While in Afghanistan, Noriega’s wife, Melissa, served in his place in the Texas House of Representatives.