PHOENIX (CN) - Democratic presidential hopeful Hillary Clinton stumped for votes at a Phoenix rally Monday, rebuking both Donald Trump and Sheriff Joe Arpaio a day before the state's presidential preference election.
Clinton currently appears certain to win Arizona and perhaps repeat her performance in the state's 2008 primary, a contest in which she soundly defeated then-U.S. Sen. Barack Obama, winning in 13 of the state's 15 counties.
Arizona pollster Bruce Merrill has Clinton winning the preferential election Tuesday with 50 percent of the vote to rival Sen. Bernie Sander's 24 percent.
However, there is still an element of uncertainty to the outcome as 26 percent of voters identified themselves as undecided.
During her appearance in Phoenix, before a crowd of about 1,500 at the city's Carl Hayden Community High School, Clinton spoke at length about her plans for immigration reform and how she plans to make the path to citizenship easier to achieve and defend the Dream Act.
"We are a nation of immigrants and exiles," Clinton said. "When I see people like Sheriff Arpaio and others who are treating fellow human beings with such disrespect, such contempt, it just makes my heart sink. We are better than that."
In 2013, a federal judge found that Arpaio, now in his seventh-term, and his Maricopa County Sheriff's Office, racially profiled Latinos and unlawfully detained them during crime-suppression sweeps.
Arpaio has endorsed Donald Trump as Republican presidential candidate, and appeared at two rallies for Trump in Arizona on Saturday.
Immigration remains a divisive issue in Arizona, which has an estimated 300,000 undocumented immigrants residing within its borders. Eligible Latino voters make up about 22 percent of voters in Arizona.
Although she didn't always evoke his name, Trump himself was also roundly criticized during Clinton's speech.
"The stakes in this election keep getting higher and higher, while the rhetoric on the other side keeps getting lower and lower," Clinton said.
"I understand that some people are incredibly frustrated ... but you know, folks, anger isn't a strategy," she said.
Before Clinton took the stage, the crowd gave a standing ovation to former U.S. Rep. Gabrielle Giffords and her husband, Mark Kelly, a retired NASA astronaut.
"Hillary Clinton is tough," Giffords told the crowd. "In the White House she will stand up to the gun lobby. That's why I'm voting for Hillary."
"Come January I want to say these two words: Madam President," Giffords said to raucous applause.
Giffords suffered a severe brain injury in January 2011 when she was shot in the head by a gunman during a meet-and-greet with constituents at a Tucson grocery store.
In the wake of the shooting, Giffords and Kelly formed Americans for Responsible Solutions, a political action committee, to support gun control legislation.
"Right now on the other side, we have a candidate for our nation's highest office that is bringing out the worst in our country," Kelly said about Trump. "The is not the America we all strive for ... one that is built on optimism and hope."
Dolores Huerta, a civil rights activist, also helped introduce Clinton at the rally.
"[Clinton's] heart is the working people, it's the people of color, it's the women and it's the young people," Huerta said before leading the crowd in chants of "Sí, se puede," or "Yes, we can."
Arizona voters have already cast about 600,000 early mail-in ballots ahead of Tuesday's preferential vote, and requested one million.
Joell Ireland, who voted for Clinton in 2008 and has again in 2016, is one of those voters.
"She believes in the things I believe it," Ireland said. "I think she will make great decisions for our country."
Lupe Rodriguez, 52, also mailed her ballot in, voting for Clinton.
"As a Latina and as a woman, there was no other candidate for me," Rodriguez said. "I know she'll put in place her ideas, which will only better me, my kids, and my grandbabies."
Abdul Izhaiman, 23, came out to the rally to listen to Clinton speak and get a better sense of her ideas, but plans to cast his vote Tuesday for Sanders.
"I'm not a supporter, I'm a fan of Bernie," Izhaiman said. "I have 100 percent trust for him."
Sanders has sunk much time and money into Arizona since last Tuesday when he held a rally at the Phoenix Convention Center. He has made five appearances throughout the state in less than a week.
About a dozen protestors congregated across from the high school, many wearing shirts or carrying signs indicating their support of Trump.
"Why would I want to support someone who has been bought and paid for?" asked Don Bolz. Bolz, 46, attended Trump's Saturday rally in Fountain Hills and voted early for the Republican presidential candidate.
The polls open at 6 a.m. Tuesday and close at 7 p.m.
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