It's very possible that both of Tuesday's primary contests will turn on Clinton and Obama's opposing positions on a temporary gas tax cut, instead of the recent media attention on Obama's former pastor.
Both have ads up on the gas tax. Clinton's is a traditional "contrast" ad:
Obama responds with a less traditional ad, featuring him in a recent town hall, mocking the proposed gas tax cut as typical Washington politics that sound good but never actually help anyone:
I noted before that Obama's best moments in the campaign have been his "adult" moments, when he is seen as "a regular voter disgusted by a system mired in pathetic childish politics."
He has employed that approach to effectively defuse negative attacks not about real issues.
This is different: an attempt to puncture stale Washington tactics regarding policy, in opposition to a populist-sounding tax cut no less.
If it works, it's a big deal.