GLENDALE, Ariz. — Vice President Kamala Harris made immigration a key component of her stump speech Friday night during a packed rally in a Phoenix suburb after making no mention of the topic during rallies this week in Michigan and Wisconsin.

“We will move forward and take on the biggest issues facing our nation, for example, the issue of immigration,” Harris told the crowd of supporters. “I was attorney general of a border state. I went after the transnational gangs, the drug cartels and human traffickers. I prosecuted them in case after case, and I won.”

During the speech, Harris reiterated her support for legislation that would strengthen border security measures and create a pathway to citizenship for undocumented immigrants. In doing so, she leaned into attacking former President Donald Trump as ineffective on border security, arguing he has prioritized electoral politics over substantive reforms.

“Donald Trump does not want to fix this problem,” she said. “Earlier this year, we had a chance to pass the toughest bipartisan border security bill in decades, but Donald Trump tanked the deal because he thought by doing that it would help him win an election.”

“We know our immigration system is broken, and we know what it takes to fix it,” Harris said to a crowd that her campaign estimated at 15,000 attendees.

Harris has faced intense scrutiny on immigration from the Trump campaign since rocketing to the top of the Democratic ticket. Republicans have focused in large part on Harris’ role in the Biden administration.

In 2021, she was tasked with addressing the “root causes” of migration to the U.S. from the Northern Triangle countries of Guatemala, El Salvador and Honduras. More recently, her GOP critics have painted a broader portrait of Harris’ responsibilities, suggesting she was tasked with bolstering border security, which did not directly fall under her purview.

Since launching her presidential bid, Harris has touched on immigration during past visits to Sun Belt states. She attacked Trump for blocking the border security bill during a rally in Georgia last month, and the Harris-Walz campaign has released ads on the topic ahead of her visits to Georgia and Arizona.

“As president, she will hire thousands more border agents,” a narrator says in an ad released Friday by the campaign. “Fixing the border is tough, so is Kamala Harris.”

In response to Harris and Walz’s visit to Arizona, the Trump campaign said in a statement that the vice president should have visited a border town.

“Border Czar Kamala Harris’ Vice-Presidential pick is just as dangerously liberal as she is,” said Halee Dobbins, Republican national committee director for Arizona, who also works for the Trump campaign. “Instead of stopping in Phoenix, Kamala Harris should be visiting our southern border and seeing the firsthand results of her border bloodbath.”

The focus on immigration comes as both campaigns are fighting for votes in Arizona. President Joe Biden won the state by about 10,000 votes in 2020, and polling suggests the race between Harris and Trump could be just as close. Additionally, Democrats’ share of the state’s electorate is down 3% during the Biden administration, according to the latest voter registration numbers by the Arizona Secretary of State’s office.

Before Harris and her running mate Tim Walz took the stage Friday night, Arizona Sen. Mark Kelly gave them a ringing endorsement. Kelly, a former astronaut and naval aviator, defended Walz, a fellow veteran, amid Republican attacks on Minnesotan’s military record. 

“He served honorably in uniform for decades,” Kelly, who had been under consideration for the role of vice presidential candidate, said of Walz.

“Tim has brought that experience to everything he has done since fighting for our service members, fighting for veterans and fighting for military families,” Kelly added, speaking alongside his wife, former Rep. Gabby Giffords. 

Democratic Rep. Ruben Gallego, a longtime ally of Harris who endorsed her during her previous presidential bid, spoke before Kelly and used his remarks to bash Kari Lake, his Republican opponent in Arizona’s Senate race this fall, and commend Walz, his former colleague in the House.

“We both served on many committees, but I know one thing about him: he always put veterans first,” said Gallego, a Marine veteran who deployed to Iraq.