Harris Has Made Up Ground in Nevada. But the Road Ahead Is Steep.

Bryce Brady, a former high school English teacher turned presidential campaign operative, took to the front of the room with first-day-of-school enthusiasm.

It had scarcely been two days since President Biden had ended his re-election bid and passed the reins to Vice President Kamala Harris, and the North Las Vegas campaign office was still plastered with Biden-Harris stickers and signs.

But every one of the dozens of volunteers in the room spoke of a newfound optimism about Ms. Harris’s chances. A few had come for the first time, suddenly happy to get involved in a race they had almost given up on.

“I know I’m preaching to the choir here, but you all maybe are talking to others in the community who say their vote doesn’t matter,” Mr. Brady said. “That could not be more false.”

He pointed to a central fact: registered nonpartisan voters now outnumber both registered Democrats and Republicans in Nevada. There would be no winning without them.

Mr. Brady compared these voters, who make up roughly a third of registered voters in the state, to drivers sitting in a parking lot. They could go either way, and choose to vote for either Ms. Harris or Donald J. Trump. Or they could just not move — they could simply stay home.