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Rocky King spent close to two years getting ready for Oct. 1.

King is executive director of CoverOregon, the state-run, online exchange that will offer health care coverage to individuals, families and companies with fewer than 50 employees. In the past two years, he's overseen building the exchange's computer infrastructure, hiring staff and training community partners.

"It's been incredible," King says. "We've got staff that have done 40 to 50 of these trainings in the past two months, and they're exhausted."

It's the latest and one of the biggest phases of health care reform, extending medical insurance through a network of state and federal marketplaces to an estimated one in five Americans younger than 65 who currently don't have coverage.

Under the new system, if you're uninsured or just shopping for better health insurance, the type of coverage available to you will depend in large part on where you live.

In all, 23 states are running their own exchanges or partnering with the federal government to offer federal-state hybrid exchanges. The remaining 27 states opted out of running their own programs, so residents of those states will have the option of enrolling through the federally run exchange.

While some Republicans are still battling to defund Obamacare, that scenario is considered unlikely. Instead, nationwide open enrollment for individuals and families in state exchanges is expected to start as planned and run through March 30 for coverage beginning in 2014.

Enrollment for small businesses opens on Oct. 1 and remains open indefinitely, regardless of where the business is located. Starting in 2015, companies with more than 50 employees either have to offer insurance or will have to pay a $2,000 fee per employee (excluding the first 30 employees).

States running their own exchanges such as Oregon, Washington and New York have spent millions of dollars in federal grants on technology infrastructure to run the marketplaces as well as awareness campaigns to publicize them.

This week, for example, the state of Washington introduced Chance, a fictional young girl and star of a $13 million ad campaign meant to acquaint residents there with its online insurance exchange, Healthplanfinder. Washington lined up more than 1,000 insurance brokers who are trained and licensed to help people evaluate plans.

Residents of New York will be able to buy insurance through existing and new providers on the state's new exchange. One new provider is Health Republic Insurance of New York, a cooperative that like other carriers will offer four tiers of coverage plus a catastrophic, high-deductible plan. The co-op claims its premiums will be among the lowest offered, ranging from an average $423.64 a month for a "Platinum" plan for a single adult down to $173.54 a month for catastrophic coverage.

In Oregon, CoverOregon will offer a total of 102 plans through 11 carriers, though most people will be eligible for a much smaller number of plans. Under a standard "Silver" plan a family of four with annual income of $32,499 to $35,324 would pay $81 to $118 in monthly premiums, with $10 copays for doctor visits and $5 copays for generic drugs. Low-income families receive subsidized insurance and might also qualify for Medicaid, tax credits or other financial assistance.

Nobody is expecting an immediate rush of signups. King estimates 217,000 people will enroll in CoverOregon's commercial insurance plans during the first year, and another 200,000 in Medicaid. "Every state anticipates we'll have low enrollment in October," King says. "They'll go and browse and shop and find out what they're eligible for."

In many states, the decision on whether to create a state exchange was politically charged. In Idaho, the state is operating its own exchange despite widespread opposition to the program. "People in Idaho don't trust the state government, but they trust Washington, D.C., even less," Eagle, Idaho, bar owner explained in a Kaiser Health News/USA Today report.

Florida has turned down millions in funds for health care expansion because of political opposition to Obamacare. The state passed a law in 2008 creating a health insurance exchange but it has not opened for business and currently does not meet federal requirements. So state residents who want to sign up will need to work through the federal exchange.

Here is a listing of which states have their own exchanges, and which will be relying on the federal exchange, according to the Kaiser Family Foundation:

State-run exchanges (16 states and the District of Columbia)

California
Colorado
Connecticut
Hawaii
Idaho
Kentucky
Maryland
Massachusetts
Minnesota
New Mexico
New York
Nevada
Oregon
Rhode Island
Vermont
Washington
Washington, D.C.

State-federal hybrid exchanges (seven states):

Arkansas
Delaware
Illinois
Iowa
Michigan
New Hampshire
West Virginia

Federally run exchange (27 states)

Alabama
Alaska
Arizona
Florida
Georgia
Indiana
Louisiana
Kansas
Maine
Mississippi
Missouri
Montana
Nebraska
New Jersey
North Carolina
North Dakota
Ohio
Oklahoma
Pennsylvania
South Carolina
South Dakota
Tennessee
Texas
Utah
Virginia
Wisconsin
Wyoming

To find out what options are available to you, check out the official government website, HealthCare.gov.

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