Incumbent Democratic Sen. Jacky Rosen and Republican opponent Sam Brown sparred on a range of topics Thursday night during their one and only face-off for the crucial battleground state of Nevada. 

The debate, hosted by KLAS, touched on the issues from immigration to abortion to recent UFO investigations.  

Both candidates were asked about immigration – a top election issue for voters across the nation this cycle.

When asked if he supported mass deportations, an idea floated by former President Donald Trump, Brown said that he supported "securing our border on day one" and backs the former president's policies on the issue.

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The Republican took a swing at Rosen on the issue, saying the senator's "own neighborhood has more security than our border."

When asked about the border, Rosen said she supported passing bipartisan border legislation and claimed that Trump is playing "political football" with the issue.

The candidates were also questioned on UFOs and whether they support more transparency on unidentified flying objects, with the debate hosts noting that Nevada is home to many claims of such sightings.

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"I think I'm just as curious as anyone. I'd love to know what's going on," Brown said. "I'm not sure I fully trust Congress to figure this out. Maybe Elon Musk can."

Rosen, who is seeking a second term in the Senate this cycle, said she thinks "its important that we do our independent investigation."

The candidates sparred on the issue of energy.

Brown tied energy and the economy together, suggesting that Rosen is prioritizing green energy projects that are raising costs.

The Democratic senator, however, touted the green energy policies passed under her leadership.

Brown said that he would not vote for any national abortion ban and that he supports Nevada's current state law on the issue.

When asked if she supports any limits on abortion, Rosen said "I support Roe v. Wade."

The debate wrapped with questions on the issue of biological males competing in women's sports. On Wednesday, Brown joined players on the Nevada Wolf Pack women’s volleyball team who refused to play against the San Jose State Spartans over the program’s biological male player. 

"I can tell you that all student athletes deserve to have a fair competition and a level playing field," Rosen said, adding that she supports "parents, coaches, and the governing leagues," deciding whether biological males should compete in women's sports.

Brown called Rosen's response "shameful."

"What we just heard was a politician say that she does not have enough knowledge on this issue," the Republican said. "I will not support biological males competing in women's sports." 

The candidates did not butt heads the entire night, both agreeing on their support for no taxes on tips, Israel's right to defend itself and affordable housing.