Now that President Obama has spoken to the joint session of Congress and Max Baucus has produced his health care proposal, attention turns to the Republicans. How will they respond to the situation, now that a certain amount of clarity has been gained? (It is, of course, only a certain amount of clarity, since some very important questions, such as whether Obama is or is not committed to the "public option," remain uncertain.)

The place to start is by remembering the basic structural difference between House and Senate. The House is ruled by the principle of virtually unrestrained majoritarianism. The Rules Committee, controlled by the majority leadership, determines how long a bill will be debated, when it will come to a vote, and how many amendments can be offered (if any). The minority has little power except what it can shame the majority into sharing—which is to say, hardly any. The Senate, on the other hand, is a more consensual body, by both its rules and its traditions. A mere majority is often not enough to prevail; the minority has a voice, sometimes even an individual senator. Under normal circumstances, to avoid a filibuster, you must either acquire 60 votes for a cloture vote or obtain a unanimous consent agreement laying out more-or-less the structure of the debate as a House rule would do, but approved by every senator. Not currently in possession of 60 votes, Democrats are threatening to apply the reconciliation process—designed for deficit reduction budget measures—to health care. Then they would only need 51 votes. However, it is not clear whether enough centrist Democrats are willing to bypass normal procedures, nor is it clear how much of any health reform bill the parliamentarian will rule in order when the use of reconciliation is challenged on the floor.

Thus the opportunities and aims of House Republicans and Senate Republicans will not be identical. House Republicans can largely dispense with a long consideration of procedural tactics. Instead, their main goal will be to make the argument against the approach of the House Democrats as vigorously as possible, citing again and again the high costs, fiscal, medical, and philosophical. Behind the scenes, they can work to pry away the 25 or so Blue Dogs who will be necessary to stop current plans.

They can also do what they have so far refrained from doing: Construct a Republican alternative. There are, of course, numerous Republican alternatives, but none the party has coalesced behind. They can attempt to put forward a unified bill, or a series of amendments. A unified bill could be much shorter, simpler, and cheaper than the Democratic bills—by itself an appealing prospect for most of the country—perhaps including insurance competition across state lines, reinsurance for catastrophic expenses, real tort reform, a small federal program to insure people with preexisting conditions (as an alternative to requiring private insurance to accept such cases), and providing individuals who want it with the same tax preference for purchasing insurance as employers currently hold alone. Amendments could include strict language prohibiting federal funding for abortions or illegal immigrants, adding tort reform, excising the public option (or turning it into a pilot demonstration project), eliminating the individual insurance mandate, and declaring that all Medicare savings must be devoting to shoring up Medicare’s own shaky finances. (Republicans here must be careful to avoid demagoguery, pretending that Medicare savings are not needed. Rather, the argument must be that those savings should be used to prevent the bankruptcy of Medicare, not serve as a piggy bank for a new entitlement program.)

Although the Rules Committee can simply write a rule that refuses to allow a substitute bill or any particular amendments to reach the floor, it will be awkward for Democrats to do so after spending months claiming falsely that Republicans have no positive ideas. An entire campaign could be launched calling on Nancy Pelosi to let the Republican proposals reach the floor. If she refuses, Republicans might be able to forge a short-term alliance with enough Blue Dogs to defeat the rule. After all, even if they do not intend to oppose a leadership-sponsored bill in the end, it is in their manifest interest to have an opportunity to obtain political cover by casting some votes for conservative amendments.

This fact, however, is the very reason Republicans in the House might be reluctant to commit themselves to an amendment strategy. The odds are that Pelosi, who enjoys a large majority, will remain in control of the situation, and will welcome an opportunity for vulnerable members of her majority to receive some cover. The Democratic leadership can simply release the maximum number of such members, whose names can revolve with each vote, that can be lost while still maintaining a bare majority. This risk is greatly diminished with a single alternative bill rather than a series of piecemeal amendments. Republicans may calculate in the end that they do not want to take that risk at all, thus forcing Democrats to take the full responsibility but leaving themselves open to charges of failure of leadership on a critical question.

In the Senate, Republicans are not biting at Max Baucus’s bill, at least not yet. Republicans’ first goal must be to dissuade Democrats from going the reconciliation route. Since this can only be accomplished by relying on the honor or sense of long-term institutional interest of a significant number of Democratic senators, it must be approached with some care. If Democrats seem determined to proceed, Republicans may have to decide whether to propose the alternative of a unanimous consent agreement, surrendering the option of filibuster in exchange for a guarantee that their amendments will be considered. Unlike the House, where alternatives would be presented with little chance of success in order to frame the debate and make life harder for Democrats, some Senate amendments might have a realistic possibility of adoption. This means the Republican calculation would be different in the Senate: Should Republicans throw what weight they have behind improving the product? Can such amendments make the Senate health care product tolerable, or would they just ease passage for a product that will still be fundamentally flawed, especially after a conference committee with Henry Waxman on it is finished? Because Senate Republicans can still affect the outcome of legislation, they face another particular challenge: there is clearly enormous political momentum for a reinvigoration of fiscal conservatism, and there is no surer way to let the air out of the balloon than by cutting a deal that makes a bad bill only slightly less bad.

Although House and Senate calculations differ in certain important respects, Republicans face a challenge that is common to both houses. Many will argue that they have a responsibility to bring something to the floor; criticism of Obamacare, though well-deserved, is not enough. While Obama and Democrats have been badly hurt by their health care proposal, Republicans have not made corresponding gains. Perhaps, in order to do this, they must fight for a compelling vision as well as against a flawed one. This view is not universally held. In the alternative conception, as the governing party in control of the presidency and both houses of Congress, Democrats are responsible for getting policy right. If they don’t, Republicans are responsible for opposing it. Ultimately, what Republicans do next will depend on which view of the role of the minority party prevails.

Andrew E. Busch is an Adjunct Fellow of the Ashbrook Center, Professor of Government at Claremont McKenna College, and Ann and Herbert W. Vaughan Visiting Fellow at the James Madison Program in American Ideals and Institutions at Princeton University.