On Arizona's border with Mexico sits the city of Nogales, where 95 % of residents have Hispanic roots, and where Republicans are hoping to capitalize on antipathy towards migrants who have recently crossed the border.

I am Mexican, 100 %, but I am against all this illegal.

I see a lot of people wanting the hand out and still coming to work.

Yvette Serino comes from a prominent democratic political family in Nogales.

We need to secure the border.

Now she's a MAGA Republican, and the chairwoman of Latinos for Lake, which supports Trump ally, Carrie Lake, in her race for the Senate.

We're just seeing so many people from like 160 different countries that don't even speak English.

The Republicans seem to be winning the messaging war on immigration, and they're even starting to gain traction with some Latino voters, many of whom are even immigrants who were not already part of the Trump base. The question is whether they'll reach enough of them to flip swing states like Arizona back to Trump.

Most Latino voters in Southwest are Mexican-Americans who have either lived in the borderlands for generations or were part of a wave of immigration that started in the 1980s. Hundreds of thousands of Arizonans live in a household where someone is undocumented. Fear that Trump will deport their loved ones still pushes many to Biden's side.

Obviously, compared to the Trump administration, Biden is better. I don't really live in that fear that I did when Trump was in office.

But this is a race with tight margins, and any erosion in support in a swing state like Arizona could be a real blow to President Biden. In a county where 60% of voters are registered Democrats, some prefer to hide their face when confessing their switching parties.

Have you always been a Republican?

No, I was the opposite, a Democrat.

Ralph preferred to keep his last name a secret.

Last time I voted for Biden, I regret because he's changing everything.

So you voted Biden, but you wish you hadn't.

Yeah, because he's failing in a lot of things. He's bringing people from all the countries around the world.

Biden recently took executive action to severely restrict asylum for migrants at the border, but it's too early to tell whether that will win over voters like retired chemical engineer Elida Carrasco. She's unhappy with Biden's handling of the border, but that doesn't translate to a vote for Trump.

Do you know who you're going to vote for?

Well, one will not be Trump.

I can assure you for that.

Let's bring in David Noriega now. So, David, talk to us about how both Biden and Trump have tried to campaign to these voters to try and swing them their way.

Yeah, Ellison. So the Biden campaign in particular has been very aggressively ramping up its outreach Latino voters, much more so than the Trump campaign. They say that they've spent about $25 million on Hispanic media outreach since last year. When you talk to particularly Democrat-leaning pollsters, analysts, and so on, they caution against overstating the extent of the shift here, overstating the extent to which Latino voters are drifting away from the Democrats and towards the Republicans. There is some polling that shows that on immigration, particularly, Latino voters are still mostly aligned with Democrats more so than Republicans. However, that used to be a really big gap between the parties among Latino voters on this issue, and that gap has definitely narrowed. There is not as much of a contrast there as there used to be. Part of that is that a lot of Latinos who live in communities with long settled immigrant populations, particularly undocumented populations, which is true of Arizona, for example, feel frustrated at the lack of reform of a pathway to citizenship for those people in addition to everything that's happening on the border. That is why in a race with such tight margins, this issue really matters.

Really, it's President Biden and the Democrats who have the most to lose. Ellison?

David Noriega, thank you.

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