It's been called a super Sunday for American politics and there's a lot at stake for President Barack Obama. The healthcare bill, one of Obama's pet projects, will be voted upon and the President has cancelled a trip to Indonesia to focus on the bill.

"We are going to get this done," a confident US President said on the eve of the historic vote, which has become a top priority for him and the defining issue of his first year in office.

Affecting virtually every American, the legislation, more than a year in the making, will extend coverage to an estimated 32 million uninsured Americans, bar insurers from denying coverage on the basis of existing medical conditions and cut federal deficits by an estimated 138 billion US dollars over a decade.

Congressional analysts estimate the cost of the two bills combined would be 940 billion US dollars over the next 10 years. But Republicans who are unanimous in their opposition say the costs will be much higher and are questioning its' reach.

"The House Republicans are determined to stand with the American people and oppose this government takeover of healthcare with everything that we got," said Mike Pence, Republican Congressman from Indiana.

The opponents gathered at Republican leadership news conference even demanded to "Kill the bill!"

But that's not all. A number of Democrats still sit on the fence, especially those pro-life. The pro-lifers worry that government could fund abortion, saying that the language of the bill is vague on abortion.

In a last minute strategy, Obama brought in an executive order on Saturday barring federal aid for abortions except for cases of rape, incest or when the mother's life is in danger.

If the bill, which is his pet project, doesn't go through it could be a huge political blow for the President Obama, whose party has a majority in both Houses.