(CNN) -- U.S. Marine Cpl. Mario Ramos-Villalta put on his freshly pressed uniform early Thursday as a citizen of El Salvador. By the end of the day, he would be a citizen of the United States of America.

Mario Ramos-Villalta earned U.S. citizenship Thursday after two combat tours in Iraq. more photos »

"I am an American," he said with a smile moments after his paperwork cleared.

"It means a lot to me after so many years and two combat deployments, I finally get it, being an American. We are happy about it."

"It's all thanks to CNN -- my news coming out, my story. That helped me out a lot," he said, referring to a story about his plight run March 20 by CNN.com. See up-close photos of Ramos-Villalta »

Ramos-Villalta, with his father at his side, went to the U.S. Citizenship and Immigration Services in downtown Los Angeles, California, where dozens of other immigrants were crowded in hopes of becoming American citizens.

Soon, Ramos-Villalta, 22, was called into an office where he answered some questions before his citizenship was finally cleared. A few hours later, he was sworn in at a naturalization ceremony with another Marine, Lance Cpl. Jose M. Tress, 23, of Mexico, and a sailor, Cpl. Marco A. Guzman, 28, of the Phillipines.

For Ramos-Villalta's dad, it was a lifelong dream: His son is the first family member to become an American citizen.

"I'm very proud of him, as is his mother, and all his brothers and sisters," Mario Ramos said. The father came to the United States from El Salvador in the 1980s.

He said his son wanted to be a member of the U.S. military since he was very young. Watch a smiling Ramos-Villalta describe "I finally got it" »

His family has always supported him, but his father said they constantly worry about him when he's in a war zone, and they don't want him to get deployed again.

"It's what he wants, but his mother and I worry about him all the time. We're always watching the news wondering if he's safe or if anything happened to him."

But Ramos-Villalta is about to deploy to Afghanistan, his third combat tour. He twice served in Iraq, where he earned a Purple Heart.

Ramos-Villalta said that finally getting citizenship lifts a huge burden, ahead of his deployment next month.

"It feels way better now. There's no more stress," he said. "I really get to fight for my country now."

Ramos-Villalta fled El Salvador's civil war in 1989 with his family as a young boy and lived in the United States for a time. Though he returned to El Salvador with his mother while his father stayed in California to work, he eventually made it back to Southern California and got his green card when he was 13.

He graduated from Santa Ana High School in Santa Ana, California, in 2004, becoming the first in his family to graduate from high school.

He then joined the Marines, becoming one of an estimated 20,500 "non-U.S. citizens" -- dubbed "green-card warriors" -- currently serving in the military.

The path to citizenship has been all the more difficult because he's been at war and wounded in action, with little time to deal with the paperwork and lawyers needed to file for citizenship.

But his new citizenship gives him hope for others in his position.

"I just hope that everybody else in the same situation gets citizenship real fast and the government can speed up the process."

The United States has tried to make it easier for foreigners serving in the military to become citizens. After the September 11 terrorist attacks, President Bush signed into law a measure allowing active-duty non-citizens who have served honorably in war on or after September 11, 2001, "to file for immediate citizenship," according to the Defense Department.

Since that time, nearly 37,000 non-citizens of the U.S. armed forces have gotten citizenship, according to the U.S. Citizenship and Immigration Services. Another 7,300 have requests still pending. It typically takes seven to 10 months to process an application.

As of Thursday, there's at least one request that is no longer pending.

"I finally get to wear the uniform of my country," he said. "I don't feel left out." E-mail to a friend

CNN's Manuel Perez contributed to this report.

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