Nor would a government shutdown likely stop it, since the federal government can rely on other sources of funding to implement Obamacare in the event of a lapse in appropriations funding, according to report this summer by the Congressional Research Center.

Whether or not Obamacare is in any peril is not something local health care providers are preoccupied with right now.

"Many of our patients have been eagerly awaiting Oct. 1," said Beatrice Bostick, CEO of Alliance Medical Center, a federally qualified health center in Healdsburg.

The health center has doubled the number of its application assistors from two to four to help get people enrolled in either Medi-Cal, the state's Medicaid program, or subsidized health insurance through the state health exchange.

About 50 percent of the health center's uninsured patients — about 1,800 people — will become eligible for insurance under the Medi-Cal expansion, Bostick said. Uninsured patients make up about 30 percent of Alliance's 12,000 current patients.

A smaller share will be eligible for "insurance products" offered through the exchange, she said.

"We've waited for this day to come and we're really looking forward to it," Bostick said.

In Sonoma County, eligibility workers at the Department of Human Services and enrollment eductors at local community health centers are among the area's most important conduits for getting people enrolled for health insurance. These workers will be taking calls from anyone who is interested in insurance, whether they qualify for Medi-Cal or not.

"We are also enrolling members of the community for both products, whether they are our patients or not," said Bostick.

Clinics are reporting full schedules for enrolling people Tuesday.

Naomi Fuchs, CEO of Santa Rosa Community Health Centers, said her organization has a roster of about 12,000 uninsured patients. About 7,500 of these patients are expected to qualify for Medi-Cal and another 1,500 for subsidies through Covered California.

"We have hired new staff to provide outreach, education and enrollment assistance so that everyone can get the health care coverage they deserve to live a healthy life and be free from fear of the costly health care services," said Fuchs.