Is being considered by a few democrats, led by John Kerry. The fact that Kerry, and not Reid or another democrat in a leadership position is leading this effort, is a clear indicator that there is not enough support for this step.
If he had one or two pro choice Republicans it would be interesting. This thin blue line will not stop Alito.
But, in a long term view, this may be a blessing for the Democrats. Polls indicated that Americans would not support Alito if he would vote to end Roe. He was never pinned down on this issue, but it is clear that Roe is done. The end effect is, when Roe is destroyed, and the public wants Roe (as it clearly does) it will give Democrats another political hammer to use against republicans. The reality is that is still years away, 2008 at the earliest, most likely 2010 or 12.
Unfortunately, the damage in the interim could do profound harm to the society, and will do profound harm to some of those who are directly effected.