Paul Nehlen. Screenshot/Paul Nehlen Youtube Paul Ryan's Tea Party-backed primary opponent released a wild new ad that consisted of his challenger, Paul Nehlen, carrying a box labeled "Drugs" across what appears to be the Rio Grande river dividing the US-Mexico border.

"Smuggling drugs into America shouldn't be this easy — but it is," Nehlen said as he carried a box labeled "Drugs" in big lettering. "Cheap Mexican heroin is killing Americans in record numbers, and it's got to stop."

"Paul Ryan's had 18 years to fix this, and he's failed," Nehlen, a Wisconsin business executive, continued. "I want to stop the cartels from killing our kids."

In a prior interview with Business Insider, Nehlen argued that Ryan has advocated for an open border.

Nehlen is facing an enormous uphill battle — one poll showed him trailing by 64 points before the August 9 primary. Ryan also boasts one of the largest campaign war chests in the nation.

The House speaker beat his last primary challenger by a massive 94% to 6% vote in 2014. His favorability among Wisconsin Republicans hovers around 70%, according to a recent poll. When just the Milwaukee media market is taken into account — which contains almost all of Ryan's district — that number inflates to nearly 80%.

Watch Nehlen's ad below: