The single number that Senate Republicans should dwell on before they vote next week on health care will not bear the imprimatur of the Congressional Budget Office. Rather the most relevant statistic comes courtesy of the Gallup poll: Democrats hold a 19-point edge (55 percent to 36 percent) as the party most trusted to handle health care.

With a majority of voters in many polls now also approving of the Affordable Care Act, the politically prudent move for Mitch McConnell would have been to develop a sudden case of amnesia about the expression “repeal and replace.” The Senate majority leader, if pressed, could always claim that the Trump family’s memory lapses about Russian ties were contagious.

Instead, McConnell has taken on the role of drum major leading the Republican march of folly. All the legislative tinkering in the world will not save the GOP from being saddled with an unpopular bill that will haunt Republican incumbents in the 2018 and 2020 elections.

Why are the Senate Republicans persisting in this desperate attempt at legislative alchemy?

No Republican on the ballot in 2018 — with the possible exception of Ted Cruz in Texas — risks retribution for a failure to repeal Obamacare. Placating Donald Trump seems a bizarre rationale since the president has already betrayed House Republicans by calling their version of the bill “mean.”

Helping the rich?

The cynical rationale had been that the Republican health care push was, in truth, a camouflaged tax cut for the affluent. All prior versions of the legislation included $231 billion in tax cuts by eliminating Barack Obama’s taxes on investment income and an upper income Medicare surcharge.

But McConnell, belatedly bowing to political atmospherics, eliminated these backdoor tax cuts from the latest version of the legislation that was unveiled Thursday. As a result, anti-tax crusaders such as Grover Norquist immediately called upon the “Senate Leadership to make it clear that those taxes will be abolished in tax reform this year.”

Another theory is that Obamacare has been the unlucky bystander in legislation that is really designed to strangle Medicaid. According to the CBO’s analysis last month of the initial Senate bill, the cutbacks in Medicaid subsidies beginning in 2020 would lead to 15 million fewer Americans being enrolled in the program in 2026.

The updated Senate bill retains these sharp Medicaid reductions, which seems a strange way to woo wavering moderate senators such as Rob Portman and Shelley Moore Capito. But, according to news reports, McConnell has been whispering that this is all boob bait for the suckers since future Congresses would almost certainly roll back these meat-cleaver cuts.

But the public assault on Medicaid would all but guarantee that health care would be a major issue in the 2020 presidential and congressional campaigns. And it is impossible to see how the Republicans would benefit from a political debate over nursing home coverage for Aunt Sally. Most Americans may not know the intricacies of health care law, but they do know that Medicaid is the last-resort safety net for the elderly who have exhausted their life savings.

So why are McConnell and company so determined to fight it out on this line?

By placating Cruz with a tweak that would allow insurers to sell health plans that cover little more than burns from volcanic eruptions, the new Senate bill invites endless horror stories about high deductibles and rejected requests for care.

The more that these fig-leaf coverage plans attract healthy Americans, the shakier the financing will be for standard policies that cover those with pre-existing conditions and higher medical costs. It is easy to imagine that a Democratic refrain in 2018 and 2020 will be, “Where are the lower premiums and the lower deductibles?”

Every time a heart-rending story about a family unable to cope with their medical bills would appear on cable TV, the president would be tempted to bat out a tweet attacking the Congress for passing such a cruel health care bill.

So what if Trump signed the legislation himself? Such glaring inconsistencies have not stopped the president from venting his rage in the past.

Misreading tea leaves

In truth, the Senate Republicans seem to be motivated by a misunderstanding of the Trump transformation. These days, traditional conservative abstractions about balanced budgets and limited government mean little to Rust Belt voters worried about jobs, health care and their children’s education.

Aside from $45 billion to fight opioid addiction (which should have been appropriated by Congress long ago), there is almost nothing in the latest Republican health care bill that will improve life for anyone. It is hard to think of any piece of major legislation that so wantonly violates the ancient medical injunction: “First, do no harm.”

If Republicans are so stubbornly wedded to their pledge to repeal Obamacare, there is a safe, albeit sneaky, way to keep this promise without jeopardizing health care coverage for millions of Americans.

All they need is to pass a single-sentence piece of legislation that reads in its entirety: “Obamacare is rescinded for now and all eternity.”

Of course, under this scheme, the actual Affordable Care Act would remain in force, offering health care coverage to millions of Americans who otherwise would live in fear of the slightest cough. And with “Obamacare” (a word that never appears in the law) out of the way, Senate Republicans could finally turn to their true love object, tax cuts.

Roll Call columnist Walter Shapiro is a veteran of Politics Daily, USA Today, Time, Newsweek and The Washington Post. Follow him on Twitter @MrWalterShapiro.