Senate Republicans have just six more days to pass a last-ditch plan to repeal the Affordable Care Act.

That is very little time — and even less when you remember the bill was introduced less than two weeks ago. But this doesn't seem to matter to Republicans desperate to make good on seven years of campaign promises. They want to avoid a Democratic filibuster by passing something on health care by the end of the month, even if it means an unusually chaotic process.

The chances for the bill known as Cassidy-Graham are still up in the air as the week begins. Although some key senators have voiced concerns (Sen. Lisa Murkowski, R-Alaska) or outright opposition (John McCain, R-Ariz., and Susan Collins, R-Maine), others who were expected to vote no have signaled new flexibility (Rand Paul, R-Ky.), putting the whip count back in flux. This has provided just enough hope to keep Sens. Bill Cassidy (R-La.) and Lindsey O. Graham (R-S.C.), the White House and GOP leaders busy trying to persuade undecided senators to support the measure.

If all of it has struck you as impulsive and haphazard, you're not alone. Here are seven ways the latest health-care effort has defied legislative norms.

• The bill was released less than two weeks ago.

Sen. Lindsey O. Graham (R-S.C.), left, speaks to the media, accompanied by Senate Majority Whip Sen. John Cornyn (R-Tex.), Sen. Bill Cassidy (R-La.), Sen. John Thune (R-S.D.) and Senate Majority Leader Mitch McConnell (R- Ky.) on Capitol Hill last week. (Alex Brandon/AP)

Republicans seemed to have given up on repealing the Affordable Care Act until about a week ago, when GOP leaders in the Senate decided to go all in on an effort to win 50 votes for Cassidy-Graham — enough to pass, as a result of the all-but-certain tiebreaking vote of Vice President Pence. Just a few days earlier, on Sept. 13, the two senators had received little attention from the media or their fellow lawmakers when they released the proposal.

If the plan does receive a vote by the end of the month, its details will have been publicly available for just over two weeks.

• The bill will have only one legislative hearing.

In a normal process, legislation restructuring the health-care system would receive months or even years of work in several congressional committees. Lawmakers would attend informational hearings about the problems health-care legislation would try to solve. They would hear from medical provider groups, patient advocates, stakeholders from the health-care industry and outside experts at every step. A bill might go through several drafts, which would receive not only hearings but markups to allow lawmakers to debate the details.

Because the Cassidy-Graham bill came about in a completely different way, it wasn't clear that it would have a single hearing until McCain and others began expressing concerns. In the end, the Senate Finance Committee met Monday to discuss the measure, with primary testimony coming from Cassidy and Graham.

• Between Cassidy and Graham, only Cassidy specializes in health policy.

It's unusual that such a significant bill would have only one sponsor who specializes in health-care policy. Cassidy is not only a doctor but he sits on the two health-oriented Senate committees (Finance, and Health, Education, Labor and Pensions). Graham sits on neither one.

• The CBO won't provide a complete score.

Most health-care bills that receive votes on Capitol Hill come with a complete analysis from Congress's nonpartisan budget analyst. These reports are designed to help lawmakers understand the likely consequences of legislation.

In the case of a health-care bill, the Congressional Budget Office typically estimates its effect on the federal budget and deficit, the number of Americans with health-care coverage and the amount insurers charge in monthly premiums. For Cassidy-Graham, however, the CBO said it would not have time to complete its normal projections. Senators will not receive the CBO's estimates on overall coverage or premium changes until later — almost certainly after any vote that might take place.

• Cassidy and Graham introduced a new version of the bill Monday.

As if the process weren't complicated enough, the bill's sponsors introduced a new version of the legislation Monday in a bid to win support from two key holdouts.

The new draft included more funding for Maine and Alaska, home of Collins and Murkowski , respectively, who have said they want to understand how Cassidy-Graham would affect their states before they vote. Previous estimates indicated the two states would lose funding under the bill.

The release of a new version means that if there is a vote, senators will have only a few days to study the legislation.

• That version won't get a complete score, either.

If the CBO couldn't produce a complete analysis of the first version of Cassidy-Graham within a week, it follows that it won't be able to do so for the second version, either. So if there's a vote, senators will have incomplete information either way.

To make things even more complicated, Cassidy has already urged people to discount the CBO's first report because it won't reflect the bill's second draft.

"Whatever the CBO scores [are] will be superseded by another score later this week," he told ABC on Sunday. "So some of what we'll be seeing [Monday] will no longer be relevant."

• To pass a bill without Democratic votes, Republicans must act by Saturday.

Senate Republicans want to pass a health-care bill before the end of the month because that is when their ability to pass budget-related legislation with a simple majority of votes will expire. Starting Oct. 1, fiscal measures will require 60 votes to pass rather than 51, a situation that would force Republicans to form a coalition with some Democrats.

In a normal process, there would be no looming deadline, and lawmakers would not be in a rush.