WASHINGTON — Democratic presidential nominee Kamala Harris heads Friday to the U.S.-Mexico border in Arizona looking to recharge her candidacy in a key battleground state where she is losing ground to former President Donald Trump.

Harris' trip to Douglas, Arizona – about 120 miles southeast of Tucson, Arizona and home to the state's second busiest port of entry – comes as a new poll released Friday by USA TODAY/Suffolk University found Trump leading Harris by 6 percentage points, 48%-42%, among likely Arizona voters. The difference is within the poll's plus or minus 4.4% margin of error.

Harris will deliver a speech at the border calling for tougher border restrictions, according to a senior Harris campaign official, who discussed the trip on the condition of anonymity.

In her remarks, she is expected to slam Trump for encouraging Republican senators earlier this year to kill a bipartisan border bill backed by the Biden administration that included tough new restrictions for asylum seekers and additional resources for Border Patrol agents. Harris has accused Trump of lobbying for the bill's defeat because he realized it would "fix a problem he wanted to run on."

But Trump has hammered Harris on the Biden administration's immigration policies and her role in addressing root causes of migration to the southern border. Immigration, a growing issue for voters, has been a weak area for Democrats and Harris.

"The worst border crisis in the history of the world," Trump said Thursday in New York. "And the architect is Kamala Harris."

More: Kamala Harris to visit southern border as immigration remains election liability

In 2020, President Joe Biden narrowly carried Arizona – which has 11 electoral votes up for grabs – by less than 11,000 voters over Trump. It was the first time Arizona voted for a Democratic presidential nominee since Bill Clinton carried the state in 1996.

But the USA TODAY/Suffolk poll found Harris trails Trump 47%-43% in Maricopa County, a bellwether and largest county in the state that includes Phoenix. In 2020, Biden carried Maricopa County 50%-48%. Trump's current polling lead over Harris in Maricopa County is within the 5.4% margin of error.

Latino support for Harris in Arizona lagging behind

It’s the latest sign that Harris is struggling to maintain momentum she gained in Arizona after taking the torch from Biden as the Democratic nominee this summer. On Monday, a new poll by the New York Times and Siena College showed Trump up by 5 points, 50%-45%, in Arizona. A Real Clear Politics average of recent polls has Trump ahead of Harris by 1.6 percentage points.

Trump campaigned at the U.S.-Mexico border last month in Sierra Vista, Arizona. Harris previously visited the southern border during a 2021 trip to El Paso, Texas.

Immigration – historically a losing issue for Democrats in elections – remains a liability for Harris even as she's gone on offense by emphasizing Trump's role in defeating the bipartisan border bill. The Harris campaign is also set to release a new television ad that will begin airing Friday in Arizona and other battleground states that says Harris will "secure our border" as president.

A USA TODAY/Suffolk University national poll this month found likely voters, by a 50%-47% margin, believe Trump would do a better job handling immigration than Harris A Quinnipiac University poll this week found Trump with a wider 53%-45% edge on immigration.

More: Harris, Trump to take part in dueling Univision town halls of Hispanic voters

Although the Harris campaign has focused efforts to galvanize Latino voters in key battlegrounds like Arizona, Nevada and Pennsylvania, the vice president’s support among Latinos in Arizona is lagging behind the national level.

Less than half – 47% – of Latino voters in Arizona said they support Harris, according to the USA TODAY/Suffolk poll. Trump has the support of 29% of Latinos in the state, the poll found. Arizona has around 1.3 million eligible Latino voters, accounting for about one-quarter of the state's electorate.

Nationally, Harris holds a larger lead among Latino voters, 57%, compared to Trump at 39%, according to a report from Pew Research.

Reach Joey Garrison on X @joeygarrion and Rebecca Morin @RebeccaMorin_