Not sure about the mulling part. Some of us were practically pounding a shoe on the podium about it in year's past ... and applauding then-candidate Obama when he sided against it in 2008. So far, the single best "alternative" is that proposed by Paul Starr. But it's a long time before the issue becomes timely, at least in terms of implementation.
Of course, it might be more of a story if someone other than Ben Nelson were doing the "mulling."