Republican lawmakers are ready to go to battle as the opening of enrollment in the Affordable Care Act's ("Obamacare") healthcare exchanges fast approaches. In the House alone, 64 Republicans have signed a letter telling Speaker John Boehner not to present items about funding Obamacare to the floor.

"This is the last stop before Obamacare fully kicks in on Jan. 1 of next year for us to refuse to fund it," said Sen. Mike Lee of Utah. "If Republicans in both houses simply refuse to vote for any continuing resolution that contains further funding for further enforcement of Obamacare, we can stop it. We can stop the individual mandate from going into effect."

In many ways, Sen. Lee is correct. Republicans can essentially "shutdown" government by refusing to vote on certain bills. According to TheHill.com, the expiration of government funding appropriation laws lands at the same time that Obamacare's healthcare exchanges are set to open, with the appropriation deadline landing on September 30 and the healthcare exchanges set to open on October 1. The GOP's goal, according to Sen. Lee, is to "[stop] the individual mandate from going into effect."

The "individual mandate" that Sen. Lee speaks of is the healthcare exchanges that the Obama administration says will help millions of uninsured. The employer mandate provision of the Affordable Care Act, which requires employers to provide health insurance coverage to their workers or face penalties, has been delayed until 2015. Now the only portion of the Act that the Obama administration remains hopeful about — the individual and small business healthcare exchanges — is under attack by Republican lawmakers. The state-run insurance exchanges would allow uninsured Americans to "shop" for the insurance plan that meets their needs. But the successful implementation of the exchanges depends on them receiving funding.

Republican Sen. Marco Rubio, who is a favorite to run for president in 2016, said that he supports a refusal to fund Obama's health care reforms. "You want to delay implementation? Don't fund it," Rubio said. "If we have a six-month continuing resolution, we should defund the implementation of Obamacare by those six months... I will not vote for a continuing resolution unless it defunds Obamacare."

But not all Republican lawmakers feel that way.

"Some would like to set up another one of these shutdown-the-government threats," said Republican Senator John McCain of Arizona. "And most Americans are really tired of those kinds of shenanigans here in Washington."

Steve Bennen of MSNBC.com predicts, like Sen. McCain, that this strategy will not bode well with the American public. In his view, the proposed government shutdown could go one of two ways: (1) the Republicans will not stage a shutdown, showing that they have no follow through or (2) Republicans will shut down government, and Americans will not be happy with the party for it.

Democratic aides who have watched the Republicans' efforts say that they are setting themselves up for failure. "I've been concerned that there could be a government shutdown and I was wondering who's going to take the blame for it, and now we know. Republicans have stepped up to the plate," said former Democratic aide Scott Lilly. For more information on the Affordable Care Act and the state-run health insurance marketplaces, go to HealthCare.gov.