With Congress moving ahead on a continuing resolution to fund the federal government for the rest of the fiscal year, some Senate Republicans are proposing an amendment to delay funding the implementation of Obamacare — and they are threatening to stop the entire continuing resolution process unless their amendment is given a vote.

The amendment is the work of Texas Republican Sen. Ted Cruz, joined by Utah Republican Sen. Mike Lee.  “I intend to object to consideration of any continuing resolution that does not include a vote to delay funding of Obamacare,” Cruz said in a press release Wednesday. Arguing that Obamacare will slow economic growth — already just 0.1 percent last quarter — Cruz added, “I believe we should continue to delay such funding at least until economic growth returns to historic averages.”

“Congress shouldn’t borrow more money to pay for something we cannot afford,” added Lee.  “Although I would prefer a full repeal of Obamacare, we should at minimum delay its implementation until our country is experiencing real, sustained economic growth.”

Senate sources say Cruz and Lee are not proposing a filibuster of the continuing resolution — which was, by the way, passed Wednesday with overwhelming Republican support in the House.  But it appears the senators want to use the threat of stopping the continuing resolution in its tracks — a tactic that could eventually lead to a government shutdown — to establish a test of opposition to Obamacare.

In the end, they will lose.  It is highly unlikely that Cruz and Lee will receive a vote on their amendment, and even if they did, it would fail in a Senate with 55 Democrats.  It is much more likely that Majority Leader Harry Reid would invoke cloture and at least 60 senators would vote to go forward over the Cruz/Lee objections and without considering their amendment.  The end of the story, according to one Senate Republican not aligned with Cruz and Lee, is simple: “Reid files cloture and people don’t want to shut down the government.”

But some Republicans, supported by some outside conservative groups, see the continuing resolution as an opportunity to keep up the fight against Obamacare.  “What we’re saying to Reid is if you give us an up-or-down vote on defunding Obamacare, we will not object to the motion to proceed on the CR,” says one Hill aide.  “That’s all we’re asking.  What Reid will do is turn this around and say, ‘Here are the Tea Party Republicans trying to filibuster the CR because they want to shut down the government unless we do something crazy like defund Obamacare.  Just move on — Obamacare is settled law.’”

That is precisely what Reid is likely to say.  But amendment supporters say that in fact some Democrats — notably the ones up for re-election in 2014 from red states — would be made uncomfortable by being forced to cast a vote on Obamacare.  That might be.  On the other hand, such a vote — requiring 60 senators to go forward over the Cruz/Lee objection — would necessarily involve at least five Republicans voting with the Democratic majority for the continuing resolution to go forward.  “This is a vote of clarity,” says the aide.  “I don’t think Lee or Cruz have a problem with clarifying who on our side is done fighting on Obamacare.  If there are folks who are raising the white flag, we should know it.”

Senate sources say the continuing resolution will likely come up for consideration next week.  In the end, if Cruz and Lee go forward, the defund-Obamacare amendment effort might yield more discord among Republicans than political damage to Democrats.