Many Americans were skeptical of GOP's Obamacare replacement even before CBO predicted losses
Erik McGregor| Pacific Press/LightRocket | Getty Images · CNBC

They weren't waiting for the CBO to have an opinion on replacing Obamacare.

Nearly half of Americans already were expecting the leading Republican health-care bill to cut the number of people with insurance even before the Congressional Budget Office estimated that 24 million more people would be uninsured if the bill becomes law, a new poll shows.

And about half of the public still opposes repealing Obamacare, as the GOP bill partially would do, according to the Kaiser Family Foundation survey that was completed Sunday, a day before the CBO's estimate was announced.

The poll released Wednesday found that 48 percent of people said the Republican plan to repeal and replace key parts of Obamacare would result in fewer people having health insurance.

That compares with just 18 percent who said the GOP's American Health Care Act, now pending in Congress, would increase the number of Americans with coverage, according to the survey.

Forty-eight percent also said they expected the GOP's bill to increase health costs for those who buy their own insurance, compared with just 23 percent who expect it to lower their costs.

Republican respondents were more likely to believe the bill would lead to increases in the number of people insured and a reduction in health-care costs.

A big majority, 75 percent, oppose a provision in the Republican plan that would cut off funding for one year for Planned Parenthood clinics to provide Medicaid services including contraception, testing and treatment for sexually transmitted diseases and cancer screenings. Several GOP senators have also expressed qualms about that provision.

Americans remain divided on the question of Obamacare repeal, with 51 percent saying Congress should not repeal the law. Another 45 percent said it should be tossed out, Kaiser's survey found.

"Views of the Affordable Care Act overall are similar to last month, with 49 percent holding a favorable view and 44 percent unfavorable," Kaiser said in a summary of the poll's results.

"As in the past, there are huge partisan divisions, with Democrats largely holding favorable views and Republicans largely holding unfavorable ones."

The poll of 1,206 people, which was conducted from March 6 through Sunday, has a margin of error of 3 percentage points.

The CBO on Monday estimated that 24 million more people would be uninsured by 2026 under the GOP's American Health Care Act if it becomes law than would be the case if Obamacare remained in its current form.

Up to 14 million more people would become uninsured by next year alone, the CBO said.