Democrats are currently trying to pass Obamacare by using a procedural rule, known as reconciliation, that would allow them to vote on the bill in the Senate and then "deem" it passed in the House. Liberals are attempting this run-around because they know healthcare won't pass a vote in both houses, and it allows the Senate to pass it with a simple 51 vote majority.
Liberals are of course screaming "They did it too" citing times where the Republican majority voted on something in the Senate. The difference is obvious of course. It has been used many times (by both parties) but is generally used as a procedural item to make things more efficient in the day-to-day practices of Congress. It has often been used for budgetary items where both houses agree on said items. This was done so that minor budgetary changes could be inserted into resolutions without the voting process being repeated each time. It has not been used for actual, highly contentious legislation.
Using it in this manner would be like the Republicans using it to pass the Patriot Act or the Iraq War Resolution. Could you imagine the uproar had they done so?
I wish I could say that Congressional Democrats and President Obama enough of a sense of self-preservation that they would avoid trying to ram healthcare through like this. I can't say that. In fact, I think they really are stupid enough to try it.
As for this practice being Constitutional, I don't see how it could be.
Article 1 Section 7 states,
Every Bill which shall have passed the House of Representatives and the Senate, shall, before it become a Law, be presented to the President of the United States; If he approve he shall sign it, but if not he shall return it, with his Objections to that House in which it shall have originated, who shall enter the Objections at large on their Journal, and proceed to reconsider it. If after such Reconsideration two thirds of that House shall agree to pass the Bill, it shall be sent, together with the Objections, to the other House, by which it shall likewise be reconsidered, and if approved by two thirds of that House, it shall become a Law. But in all such Cases the Votes of both Houses shall be determined by Yeas and Nays, and the Names of the Persons voting for and against the Bill shall be entered on the Journal of each House respectively
Keeping Article 1 Section 7 in mind, here's what the Democrats plan to do, as explained in this CNN article,
"The emerging consensus plan is for the House of Representatives to pass the Senate bill and send it to Obama. A package of changes that mirror the president's plan would then be passed through both chambers under reconciliation rules.
What the Democrats are doing is trying to avoid an up or down vote on a finalized bill. They want to pass an unfinished bill, send it to Obama, then use reconciliation to pass the bill with "amendments". "Amendments" meaning all of the crap they want in the legislation but can't actually get passed. It seems obvious that under this strategy the legislation will not be voted on by both parties, as required by Article 1 Section 7.