SANTA CLARA -- In the bright morning sunshine, they stood as one and raised their right hands. Then with strong, clear voices, 79 men and women from 20 countries together recited the words they had dreamed for years of speaking:

The Oath of Allegiance.

Aileen Dela Cruz was beaming.

"Now, I feel complete," said Dela Cruz, a 31-year-old registered nurse from the Philippines, afterward. "I'm so proud."

With the picturesque double-decker carousel of California's Great America theme park in the background on Thursday, a brand new group of full-fledged citizens of these United States celebrated the moment with friends and family in a flood of cheers, and some tears.

Each story was unique. Some were young, some older. They came from Brazil, Ethiopia, New Zealand, Venezuela and other places around the globe. They shared a common goal. All had come to this country in the search of opportunity -- and to become Americans.

This ceremony was part of the U.S. Citizenship and Immigration Services annual celebration to mark Independence Day. An estimated 9,000 people have been taking the oath at more than 100 naturalization events across the country this week, including at historical sites such as the Mount Rushmore National Memorial in South Dakota and the USS Missouri in Pearl Harbor, Hawaii.

At the Santa Clara amusement park, it was a festive setting: Great America honoring new Americans.

The events are coming at a time when the hot-button issue of immigration remains one of the country's most politically divisive debates. Thursday, though, was one of those moments of pure, unbridled joy when newcomers took the climactic step in a long journey by joining the nation's family.

Alberto Mejia, 34, of Salinas, stared at his Certificate of Naturalization, a look of amazement on his face.

"It feels like I'm on a different planet now," said Mejia, a public works construction manager with Monterey County who came from Mexico at age 13 with his family. "I feel so good." He paused. "Finally."

Nearby, Peggy Chiang, 20, a Cupertino High School graduate and Cal Poly student, said she has been in the United States since age 8 when her family emigrated from Taiwan -- always feeling more American than Taiwanese. Chiang said she became emotional at the end of the ceremony when, in a taped message, President Barack Obama welcomed them as citizens.

"I felt like he was talking directly to me," said Chiang, whose parents took the oath last month. "This is supercool. It's nice to officially call this my home now."

So far this year, more than 414,000 people have been naturalized. Rep. Mike Honda, D-San Jose, told the Santa Clara group that he knew each of their paths had been unique. But now they had arrived at a place where they were the same as every other American -- equal.

"America is the land of the free and the home of the brave, but it's also a nation of diversity," Honda said. "Many of you came for the promise of a better life for yourselves and your children. The journey has been very long and sometimes uncertain. But your journey hasn't ended. It really has just begun as you are now part of this country."

These new Americans repeated the same point, again and again, about why citizenship was so important: The right to vote.

Zhipu Jin, 39, is a Silicon Valley software engineer who came to this country 13 years ago from China to attend Caltech in Pasadena.

"The most important thing is that I want to participate as a member of my community and society," he said. "With a green card, I just didn't feel like I'm truly part of the nation. I really wanted to express my opinion, and unless I could vote, I couldn't do that."

That sentiment was echoed by Jose Ortiz, 29, who came here with his family from Mexico when he was 4 years old and graduated from San Jose's Independence High School.

"I want to be able to vote and make my voice heard," said Ortiz, an office administrator.

Dela Cruz, a Santa Clara resident, took personally the section of the oath that states, "I will bear arms on behalf of the United States when required by the law." Her husband, Kristian, is an Air Force technical sergeant who also is from the Philippines and became a citizen through his military service.

"My husband has fought for his country," she said. "I have such a high admiration for the military and support our veterans. I want to be able to defend the country."

After the ceremony, their 1-year-old son, Michael, happily waved a little American flag as other new citizens posed for photographs with Honda and in front of a huge flag.

Outside the park, lines already were forming to enter for a day of fun as the country headed into the long Fourth of July weekend. The new citizens were invited to stay as guests of Great America. But some, certificates in hand, left into a world that, for them, had been forever changed.

Follow Mark Emmons at Twitter.com/markedwinemmons.