The White House description of President Obama’s health care proposal as his “opening bid” raises the question: With whom is he bidding? The public dance is with Republicans, but this is hardly serious. The White House does not enter Thursday’s summit expecting Republicans to make a deal.

So the real target of presidential bidding is with his own party — specifically House Democrats. The White House hopes that Blair House will turn out to be the new Baltimore, a venue, like Obama’s meeting with the Republican caucus, where a nimble president debates the opposition and wins. Not with the other party but with the public, thus stiffening Democratic spines for the difficult legislative road ahead.

In Monday’s blueprint, the president made the decision — certainly audacious and perhaps foolhardy — to press for the comprehensive, near-trillion-dollar package. Getting there would require a two-part solution. The Senate, using the majority-vote process of reconciliation, would tweak the measure along the lines suggested by the president. The House would pass both the tweaks and the underlying Senate bill.

The arithmetic of this approach is unforgiving. Even before the shock of losing the Massachusetts Senate seat, there was no margin for error in either house. This remains true, except the politics in both chambers have become that much harder.

First, the Senate. The House wants it to take the lead, for a change. But for parliamentary reasons, this is unlikely. No matter what the order, getting the measure through the Senate even under a majority-vote rule will be a challenge. Some Democrats are reluctant to take this divisive step. Assuming enough can be brought along, Republicans will still have the ability, even under reconciliation rules, to bring the Senate to a virtual standstill.

That would be the easy part.

In the House, the only way to cobble together a majority will be to secure votes from moderate Democrats who balked at passing the bill the first time around. These are the lawmakers who are the most rattled by the Massachusetts vote — with good reason. For a Democratic House member in a swing district, the politics counsel against voting yes. “This is a career-ending vote,” one Democrat told me — and this was a lawmaker who voted for the original bill.

With the House down a few members, 217 votes will be needed for passage. The original House measure passed with 220 votes — with 39 Democrats defecting. But two of those yes votes are gone: John Murtha of Pennsylvania died; Robert Wexler of Florida resigned. A third, Neil Abercrombie of Hawaii, is leaving at the end of the month to run for governor. The lone Republican voting for the measure, Joseph Cao of Louisiana, is no longer on board.

Meanwhile, the president’s proposal does not include the anti-abortion language inserted in the House-passed measure by Rep. Bart Stupak, D-Mich., largely because the Senate would have difficulty fiddling with its abortion language under the restrictive rules of the reconciliation process. So Stupak will be gone, and with him another five votes, perhaps even more.

There are a few liberal lawmakers who might be wooed back — Ohio’s Dennis Kucinich, for instance, voted against the first version — but not enough to make up the difference. So the fate of the measure rests with the conservative Democratic Blue Dogs. A few are retiring — including John Tanner and Bart Gordon of Tennessee — and might be persuaded to switch their votes. This would help, but likely not be enough.

Will other Democrats switch? The president’s blueprint is more moderate than the House measure but more expensive and less tough on cost control than the Senate version. According to one person present, at her meeting with House Democrats Monday night, Speaker Nancy Pelosi was bragging that 80 percent of the excise tax on high-cost insurance plans — a central cost control measure that is hated by House liberals — had been eliminated. Meanwhile, more and more Democratic senators are signing on to a letter urging that the public option be included as part of the Senate’s reconciliation package. None of this seems conducive to securing moderate votes.

Maybe the president can pull this off. My worry is that going for broke and failing will not leave time or appetite for a fallback, scaled-down plan. And the moment to do something on health care — not everything, but something significant — will have evaporated, once again.

Ruth Marcus’ e-mail address is marcusr(at symbol)

© 2010, Washington Post Writers Group

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