LOS ANGELES >> Vice President Kamala Harris was set to rally in Las Vegas on Sunday night as both she and Republican Donald Trump continue to frequent Nevada, looking to gain momentum in the swing state as Election Day nears.

The rally is part of Harris’ latest West Coast swing, which included making her first trip to the U.S.-Mexico border since taking over for President Joe Biden atop the Democratic presidential ticket, where she walked alongside a towering, rust-colored border wall fitted with barbed wire in Douglas, Arizona, and met with federal authorities.

Harris’ four-day trip was crafted with dual purposes: She was opening and closing the trip with stops in the Sun Belt battlegrounds of Arizona and Nevada, where the vice president is trying to shore up support as Trump pounds her relentlessly over illegal migration. And her mid-stay in California was devoted to hauling in campaign contributions from donors in her blue home state.

“This race is as close as it could possibly be,” she said Saturday to a raucous crowd of donors. “This is a margin-of-error race.”

Harris said even if there is enthusiasm, she’s running like an underdog. And she invited people to “join our team in battleground states” to help get voters to the polls — even if it’s Californians making calls from home.

Her border visit seemed to get under Trump’s skin. The GOP leader spent two days railing about Harris at two separate rallies, upping his personal attacks against her, claiming she was responsible for a border “invasion,” and stirring up unfounded fears that she’d usher in lawlessness if elected.

On Sunday, former Arizona Sen. Jeff Flake became the latest prominent Republican to endorse Harris and Walz. He credited them with a “fine character and love of country” and said he wants a president who does not treat political adversaries as enemies or try to subvert the will of voters.

Flake, a longtime critic of the former president, joins a list of anti-Trump Republicans who have said they will vote for the Democratic ticket, not just refrain from voting for Trump. Among them is Dick Cheney, the deeply conservative former vice president, and his daughter, Liz.

But Maryland Senate candidate Larry Hogan, a former Republican governor and a sharp critic of Trump, said Harris has yet to earn his vote, though Trump won’t get it.

In Nevada, all voters automatically receive ballots by mail unless they opt out — a pandemic-era change that was set in state law. That means most ballots could start going out in a matter of weeks, well before Election Day on Nov. 5.

Harris heads back to Las Vegas on Oct. 10 for a town hall with Hispanic voters. Both she and Trump have campaigned frequently in the city, highlighting the critical role that Nevada, and its mere six votes in the Electoral College, could play in deciding an election expected to be exceedingly close.