PHOENIX (AP) — Democrat Ruben Gallego held the first public events of his U.S. Senate campaign Saturday, taking aim at independent incumbent Kyrsten Sinema and casting his candidacy in a patriotic appeal to the American dream.

The fifth-term congressman recounted his journey from a poor family in Chicago to cleaning toilets as a Harvard student and a tough combat deployment as a U.S. Marine in Iraq.

“I knew if I worked hard and I kept my nose clean, this Latino kid was going to succeed in America. And I did,” Gallego told a crowd of several hundred supporters in Grant Park, a Central Phoenix hub of Latino political organizing.

Gallego began his campaign on Monday with a video posted to social media and embarked on a national media tour before returning to Arizona. In addition to his Phoenix rally on Saturday, he made similar appearances in Tucson and Casa Grande, and he planned stops Sunday in Flagstaff, the Navajo Nation and the reservation for the White Mountain Apache Tribe.

Gallego is facing the toughest campaign of his political career. Since winning a tough primary for his overwhelmingly Democratic congressional district in 2014, he’s never faced serious opposition. He now must introduce himself to voters outside his Phoenix district.

He touted his military service and his against-the-odds biography, saying that in many ways he’s “the product of that American dream.” But he pointed to the death of Tyré Nichols at the hands of five Memphis police officers as evidence there’s more work to do.

“The American dream has to include people like Tyré Nichols,” Gallego said. “It has to include Black men living without fear, and being able to live, period. They deserve the American dream, too.”

Sinema was elected as a Democrat in 2018 but left the party late last year, registering as an independent after years of growing estrangement from the party. She has not said whether she will run for reelection.

“The problem with Kyrsten isn’t that she left the Democratic Party,” Gallego said. “The problem is that she left and abandoned Arizona.”

Sinema has not directly commented on Gallego’s entrance in the race, but on Twitter last week she touted the bipartisan deals she’s helped negotiate and suggested campaigns can wait.

“Arizona just got through a brutal election season — I think we all could use a break,” Sinema wrote. “As I did with infrastructure, tribal water security, drought relief, LGBTQ+ rights, Chips, and so much more, I’m going to keep making good on my promise to deliver real results for our state.”

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