LAS VEGAS – Progressive caucus co-chair Rep. Raúl Grijalva (D-AZ) on Saturday issued an ultimatum to opponents of a public option who invoke deficit concerns: get behind this program, or you’re hypocrites.

In an exclusive interview with Raw Story at Netroots Nation, a large conference for progressive activists and media, Grijalva lamented how "one of the most important mechanisms [to cut the deficit] was left out of the [health reform] bill."

But he and more than 120 other members of Congress revived the idea in legislation introduced Thursday, which is projected to save billions of dollars. And they’re using that to challenge the GOP and conservative Democrats, who have claimed it'll be too costly, to get behind it.

"You’re the deficit hawks," Grijalva said, referring specifically to Republicans and Blue Dog Democrats, "and we're giving you a tool to be able to deal with the deficit."

The measure would offer consumers the choice of a public plan alongside private plans in the insurance exchanges set up by the sweeping health reform law enacted in March. The nonpartisan Congressional Budget Office projected that it would reduce insurance costs and lower the federal deficit by $68 billion through 2020.

In the wake of the CBO estimates, and amidst a climate of increasing concerns about the national debt, Grijalva charged that self-styled deficit hawks against the measure are inherently being disingenuous, if not worse.

"They’re hypocrites," Grijalva said. "Basically, they’re against the public option, period, for philosophical reasons, and the excuse that it was going to be too expensive is phony. They're phonies."

Conservatives have also derided the public option as simply more government, and warned that it would be a slippery slope to a single payer, Medicare for all-type system.

The Arizona congressman, who was initially wary of supporting a health care bill without a strong public option, said the deficit issue would help progressives win the requisite support this time in Congress.

"We have two arguments going for us," he said. "Popular support, which we've always had, and then the realization that if we're going to do something about the deficit, that one of the most important mechanisms was left out of the bill."

The provision faces steep odds for the remainder of this Congress, with the November midterm elections approaching. But Grijalva said the progressive caucus won't stop fighting next year.