Washington (CNN) - A growing chorus of high-profile tea party leaders is threatening Republican lawmakers: Defund Obamacare or get a primary challenge.
Three conservative Republican senators, a handful of House members and even more tea party activists took to a stage on the West Lawn of the U.S. Capitol Building Tuesday afternoon to protest the implementation of the Affordable Care Act. But their call to action–and their anger–was directed more at the Republican leadership in the House than at President Obama.
One sign in the crowd read: "Hey, GOP. The end is near for Obamacare or you. Your choice."
The law was enacted in March of 2010, and one of its largest pieces – insurance exchanges – are set to open to the public on Oct. 1. Some Republicans, though, are still looking for ways to stop the law from taking effect, and they're pressing their leadership to defund the law by not passing the continuing resolution that funds the government.
More moderate Republicans, particularly in the Senate, say that strategy is foolish, but the tea party complains that not trying is spineless.
Republican Sen. Mike Lee of Utah said, "If you fund this law, you are for it."
His Kentucky colleague Rand Paul added, "We need some backbone up here; we need some help." He went on, "We don't need to be invertebrate caucus, we need to be the caucus with a spine."
And the last senator on the stage – Ted Cruz of Texas – said, "Some Republicans are considering procedural tricks." He asked the crowd, "Is an empty symbolic vote enough?" and, "Are tricks and games acceptable?"
House Republican leaders Tuesday introduced to the GOP rank and file legislation that would fund the government through mid-December. In an attempt to give conservative members cover and to secure votes, Republican leaders are also drafting a proposal that would be voted on alongside the funding bill. The separate measure would contain language preventing the administration from using any federal funds to implement the new health care law. A House vote on both these measures could come as early as Thursday.
A senior House GOP aide admitted to CNN Monday night that the language on defunding Obamacare would be non-binding.
The list of tea party leaders routinely criticized House Speaker John Boehner and House Republican Leader Eric Cantor for passing responsibility to the Senate.
Every time each House leader's name was mentioned, the crowd of at least 1,000 jeered.
And Brent Bozell of the conservative group, ForAmerica, promised Republican legislators: "To those rank and file members playing this three card Monte game, I can say only one thing: Get ready for some primaries."
- CNN’s Paul Steinhauser and Deirdre Walsh contributed to this report.