Harris Rides Momentum to Arizona, for What Campaign Says Is Largest Rally Yet

Vice President Kamala Harris rolled into Arizona on Friday evening with the same political momentum that has infused her first swing across the country this week, drawing a crowd that her campaign estimated at more than 15,000 — her largest yet — in a Western state that not long ago appeared to be falling off the battleground map.

Along with her newly minted running mate, Gov. Tim Walz of Minnesota, Ms. Harris delivered a stump speech that is barely a week old, and yet familiar enough to an impassioned new following that some shouted her lines before she did.

The rally was her fourth in four days with an arena-filling crowd that demonstrated the degree to which her candidacy replacing President Biden’s had remade the 2024 race.

Mr. Walz relished the crowd that filed into the Desert Diamond Arena in Glendale, Ariz., in 100-degree heat as he poked fun at Mr. Trump’s obsession with rally crowds.

“It’s not as if anybody cares about crowd sizes or anything,” Mr. Walz said to knowing cheers.

Despite her momentum, Ms. Harris faces an uphill battle in Arizona, a longtime Republican stronghold that flipped to Mr. Biden in 2020 but, according to polling, had been drifting back to former President Donald J. Trump this year.

To win, she will need to reunite the diverse coalition of voters who delivered the state four years ago, and she made an explicit appeal to one part of that group on Friday: Native American voters.