On Friday, House Majority Leader Eric Cantor (R-Va.) is gathering key members of his caucus to work toward coming up with a single, official Republican alternative to the Democrats' Affordable Care Act (ACA), or ObamaCare. Republican lawmakers have several competing bills to work with, and putting the party's weight behind one plan or piece of legislation would be great for the country: Finally, America could have a real discussion about the best way to reform America's health care insurance system.

But an official Republican health care plan would also be great for Democrats — which is reason No. 1 Republicans aren't going to actually rally behind a single plan.

They will, of course, make a public effort. "GOP leaders have been clear that ahead of the 2014 elections, the conference wants to show what it is for, not simply what it is against," says Daniel Newhauser at Roll Call. "Similarly, they want to show that they are not in favor of simply returning to the old health care system, which is viewed unfavorably by the electorate." But any viable plan needs 218 votes from the fractured GOP caucus.

Cantor and his fellow House Republicans have at least three separate House bills to consider — from Reps. Tom Price (R-Ga.), Paul Broun (R-Ga.), and Phil Roe (R-Tenn.) — and a plan from Sens. Tom Coburn (R-Okla.), Richard Burr (R-N.C.), and Orrin Hatch (R-Utah) that was unveiled to much fanfare in January. There's also a bill, from Rep. Todd Young (R-Ind.), that would raise ObamaCare's definition of full-time employment to 40 hours a week, from 30. And a George W. Bush administration economist named Edward Lazear is pushing what he calls BushCare.

As they sort through these plans, what criteria will they use? If they can agree on one proposal, says Roll Call's Newhauser, it's "likely to include poll-tested measures that have broad agreement in the GOP conference, including allowing the purchase of health insurance across state lines, allowing insurance portability between jobs, expanding access to health savings accounts, and limiting medical malpractice lawsuits."

Another way of putting that: Republicans are looking for popular talking points that sound different enough from ObamaCare to win support from the more conservative factions of the GOP caucus. The problem, as The Washington Post notes, is that "there are only so many ways to preserve the patient protections that the ACA offers, which Republicans say they want to keep, while maintaining a private insurance market and assisting those who can't afford coverage."

Once Republicans hold up a specific plan, the Congressional Budget Office gets to issue its verdict and the public gets to weigh the proposals not just against ObamaCare but also the GOP's attacks against ObamaCare.

The CBO analysis for Rep. Young's bill to raise full-time employment to 40 hours, for example, found that the bill would raise the federal deficit by $74 billion while reducing the number of people getting employer-sponsored health insurance by about a million; about half of those people would go on Medicaid or other public programs, the other half would be uninsured.

It's not clear the other Republican proposals would be popular in practice, either. Some of them, as the Washington Post editors note, would be better than ObamaCare at holding down health care costs and incentivizing people to buy private health insurance. But they are more disruptive to the status quo — especially post-ObamaCare — and almost all of them would be ripe for articles about sick people losing coverage or watching their health insurance costs skyrocket.

All of the GOP alternative plans, in other words, have their own drawbacks. Some people will lose, and some people will win. They would reduce the role of the federal government in most cases, but increase the power of insurance companies. Many of the policies are really interesting. Here are some examples of the big ideas from the GOP plans:

Cap or end employer tax breaks for providing health insurance: The idea here is that the insurance market is distorted by the tax incentives for employers to offering their workers insurance. It's a fair point. But capping the tax breaks, as Coburn-Burr-Hatch does, or eliminating them would almost certainly cause employers to drop their plans. Almost 60 percent of Americans get their health insurance through work.

Provide tax breaks for individuals to buy their own insurance: With no employer-offered health plans, individuals and families would buy their own insurance on the open market. The Coburn-Burr-Hatch plan, for example, offers age-adjusted tax credits to people at up to 300 percent of the federal poverty line: Individuals 18 to 34 would get $1,560 a year, while those 50 to 64 would get $3,720 a year (families would get more than double those figures). Lazear's BushCare would give all Americans with any type of health insurance $7,500 a year in tax breaks, or $15,000 for families; if people opted to buy low-cost, low-coverage insurance, they'd pocket the difference.

Allow insurance to be sold across state lines: This is a perennial GOP proposal to lower health insurance costs. The idea is that if insurers could sell the same policies to any state, regardless of that state's own insurance regulations, it would increase market competition and drive down prices. A 2005 CBO report estimated those savings to consumers at about 5 percent overall, with the savings skewed toward the young and healthy; the old and sick would pay more. Enacting this option would require scrapping the minimum standards required for all plans under ObamaCare — a selling point for conservatives who argue we use too much health care, anyway.

"The fact that Republicans are coalescing around healthcare reform plans of their own could be very bad news for ObamaCare," says Sally C. Pipes at Forbes. "Once voters see that the Republican alternative adds up to sensible and affordable health care, ObamaCare's days will be numbered."

But the opposite is almost certainly true. And House Republicans known that.

The GOP has gotten a lot of mileage out of its push to repeal ObamaCare — with a big assist, since October, from the Obama administration — but now the law is signing up real people (four million and counting) for real insurance policies. Republicans have to do better than provide plausible-sounding alternatives. They have to come up with a plan that Americans will think is much better than ObamaCare, and worth the disruption of overhauling the health care system again.

Here's the bottom line: If reforming America's health care system to provide near-universal affordable coverage were easy, it would have been done 60 years ago — or at any point since. Several Democratic presidents had tried and failed before President Obama. If Republicans had wanted to take their own bite at the apple, they had plenty of chances, too.

This isn't spitballing. If Republicans want to be relevant voices in the health care debate, they have to come up with something. They should come up with a plan they can try to sell to America.

"One of the unseemly aspects of the last four-plus months is watching some on the right root for ObamaCare to fail," says Forbes' Avik Roy, one of ObamaCare's wonkiest critics. Among some conservatives, "there has been a kind of intellectual laziness, a belief that there's no need for critics to come up with better reforms, because Obamacare will 'collapse under its own weight,' relieving them of that responsibility." But it's clear now that's not going to happen, he adds. "And that makes the development of a credible, market-oriented health-reform agenda more urgent than ever."

Well, don't hold your breath.

The Affordable Care Act was written and enacted by Democrats — with a few exceptions — and that's one of its main weaknesses: If Republicans had helped shape and pass the law, they probably wouldn't have spent the last four years attacking and undermining it. They now have at least 10 months left to criticize the law without having to take any serious action to replace it. Don't expect them to squander the opportunity.