WASHINGTON — Indiana’s Democratic lawmakers are keeping their opinions on the House’s health-care reform bill to themselves.

It’s unclear whether a majority of the delegation — or even a majority of the state’s Democrats — will support the biggest expansion of the nation’s health-care system in decades. The state’s four House Republicans oppose the overhaul that the chamber could vote on today or Sunday.

Indiana’s five Democrats have not said how they will vote on the bill, which is a top priority for President Barack Obama.

Rep. Baron Hill, for example, voted for an earlier version of the bill and recently told a Democratic audience the time has come to reform the nation’s health-care system. But the Democrat from southeastern Indiana said he is reviewing the latest version.

Rep. Andre Carson has stressed the need to reduce the ranks of the uninsured, which are higher than average in his Indianapolis-based district. But Carson also wants a stronger government-run public insurance plan than the version in the bill. Carson is supportive of the bill but wants to see if there are any changes before the vote, according to his spokesman.

Rep. Brad Ellsworth, D-Evansville, has been working on changing how the bill would prevent federal funds from paying for abortions for women whose insurance is subsidized by the government. Even if Democratic leaders incorporate those changes, Ellsworth has not committed to voting for the bill.

Hill, Ellsworth and Rep. Joe Donnelly, D-Granger, represent politically competitive districts that often are targeted for takeover by the other party.

“The average American can’t name his or her member of Congress or cite an element of his or her voting record,” said Robert Dion, a political science professor at the University of Evansville. “But this one will get their attention.”

Lawmakers also might be considering how the bill would affect major industry players based in Indiana.

Indianapolis-based WellPoint, the nation’s largest U.S. commercial insurer in terms of membership, opposes the bill.

Eli Lilly and Co. prefers a Senate version but has not urged Indiana’s House members to vote one way or the other, according to a Lilly spokesman.

Gov. Mitch Daniels, a Republican, encouraged delegates to vote against the bill, in part because it would expand Medicaid, the federal-state health-care program for the poor. The federal government would pay for most of the expansion, but Daniels said Indiana’s share would still be too much.

More than 744,000 Hoosiers — about 12 percent of the state’s population — don’t have health insurance, compared with 15 percent of U.S. residents who are uninsured, according to the Kaiser Family Foundation.

The House bill would spend $1.1 trillion over 10 years insuring 36 million more Americans. That cost would be offset through new taxes, spending cuts in Medicare and Medicaid and penalties levied on people and businesses that don’t buy insurance. As a result of those provisions, the bill would reduce the deficit by $129 billion.

An alternative health-care proposal offered by House Republicans would cost less than the Democratic plans and insure far fewer people.

“(Democrats are) launching this massive expansion of government bureaucracy, taxes and mandates to achieve what they call universal coverage, which is their every right to pursue,” said Indiana Rep. Mike Pence, the third-ranking member of the House GOP leadership. “We believe the American people are most concerned about the cost of health insurance, the cost of health care, and so our plans are designed to bring down the cost using the power of the individual.”

What it could mean for you

The uninsured

Most people would have to buy insurance or pay a penalty equal to 2.5 percent of their income, starting in 2013. Some could get help through Medicaid, the federal-state health insurance program for the poor.

Eligibility for Medicaid would expand to cover people earning up to 150 percent of the federal poverty level ($33,075 for a family of four).

The insured

Insurance plans would have to meet minimum benefit standards and other new regulations, including:

A ban on denying coverage based on a pre-existing condition.

No annual or lifetime caps on coverage.

No co-pays for preventive care.

A ban on charging more based on health status, gender or occupation.

Annual limits ($5,000 for an individual and $10,000 for a family) on how much customers would have to pay each year in co-pays and other out-of-pocket expenses.

A requirement that insurance companies justify premium increases.

Women

A ban on charging women more than men.

Younger adults

Parents could keep their children on the family’s health coverage until the child’s 27th birthday.

Seniors

Limits on how much more older people could be charged than younger people for the same coverage.

Brand-name drug prices would be cut in half for seniors who fall into the “doughnut hole” gap in Medicare drug coverage. The government now pays up to a certain amount a year for drug coverage for seniors. Once that amount is reached, seniors are responsible for paying the full cost until those payments reach a limit. This coverage gap would narrow and eventually disappear by 2019.

Seniors who get their Medicare coverage through the Medicare Advantage program could see changes. The bills would reduce the subsidies insurers get from the government to offer the plans. That could prompt some companies to stop offering the plans or to cut back on the benefits offered.

Businesses

Businesses with payrolls of more than $500,000 would have to offer coverage to workers by 2018 or pay a penalty.

Businesses with up to 25 employees could purchase insurance for them on the health exchange starting in 2013. Eligibility would expand to companies with up to 100 employees by 2015 and could expand further after that.

The wealthy

Individuals earning more than $500,000 and couples earning more than $1 million would be taxed an additional 5.4 percent on any income above that amount.

States

After 2014, states would have to pay 9 percent of the cost of expanding Medicaid.

People contributing to health spending accounts

Contributions to the tax-free flexible spending accounts would be limited to $2,500 a year, indexed to inflation.

— Maureen Groppe