Rep. Dana Rohrabacher (R., Calif.) has run up a nine-point lead over Democratic challenger Harley Rouda in his traditionally conservative Orange County district that Democrats are heavily targeting this year.

The strong margin for Rohrabacher, coming just days before Tuesday's midterm elections, has political analysts declaring the district a "firewall" to the Democrats' predictions of a blue wave rushing through California and sweeping Democrats into the House majority.

"While California overall breaks in favor of Democrats and against [President] Trump, CA-48 is proving to be the firewall holding back the blue wave," TPStrat Research's John Thomas said of the polling data, which the firm conducted Oct. 18 through Oct. 31.

Despite TPStrat's statewide generic ballot revealing a heavy Democratic advantage in the midterm elections throughout the state, "thus far, the 48th [Congressional District] appears to be immune to such negative gravity. Trump is popular, Republicans are winning the generic ballot and there is a slight edge for the amount of voters who want Trump's agenda to be pushed in Congress," he said in his analysis.

"This seat is proving reliably red," he added.

The survey was paid for and commissioned independent of any campaign or committee, the firm said.

With the latest positive economic news, Trump's approval rating is at 56 percent in the district, and a generic ballot gives Republicans a 10 percent advantage over Democrats. The survey also showed that 49 percent of voters in the district want Congress to support Trump's agenda.

Rohrabacher has maintained this 9 percent lead for two weeks in a row, at the same time Trump's approval ratings averaged 55 percent.

The new polling is a splash of cold water on Democratic hopes to oust Rohrabacher, an eccentric libertarian and Trump ally who has held the seat for nearly 30 years. Earlier this week, the Los Angeles Times ran a story with the headline, "In deepest red Orange County, a blue flame is sparking in a district that has long supported Rep. Rohrabacher."

Despite his personal wealth and telegenic appearance, Rouda has not attracted the groundswell of Democratic support many party operatives expected. He has been hit with a series of negative ads for firing a cancer victim from the real-estate firm he previously ran and sold to make his millions. The firm also failed to disclose to franchisees of the real-estate company that a jury in 2008 had sided with the 57-year-old cancer patient and awarded her $1.85 million, the Washington Free Beacon reported.

Rouda in recent months tried to walk back his repeated primary support for impeaching Trump, as well as his previously unequivocal backing of expanding Medicare to illegal immigrants, Medicare for all and several other liberal positions, such as creating a Department of Peacebuilding in the federal government.