They better be able to back this up, because as a friend observed, this is real scorched earth stuff.

Statement from Obama campaign manager David Plouffe

We currently have reports of over 200 separate incidents of trouble at caucus sites, including doors being closed up to thirty minutes early, registration forms running out so people were turned away, and ID being requested and checked in a non-uniform fashion. This is in addition to the Clinton campaign’s efforts to confuse voters and call into question the at-large caucus sites which clearly had an affect on turnout at these locations. These kinds of Clinton campaign tactics were part of an entire week’s worth of false, divisive, attacks designed to mislead caucus-goers and discredit the caucus itself.

Also, I wouldn't believe Obama's spin that despite losing the popular vote Obama received one more delegate than Clinton. From Digby:

P.S.S.S. OK, I just spoke with Jill Derby, the head of the Nevada State Democratic Party. Regarding the Obama claim that he'll actually get more delegates out of this, essentially that's spin. Derby said that the caucuses are an "expression of the support of Nevadans today." Around 11,000 delegates were elected today. That will be winnowed down at county conventions and eventually at the state convention in May to the 25 that will go to Denver for the DNC. In 2004, Kerry didn't win every delegate on Election Day, but most of the delegates that eventually went to the DNC were his. Once there's a presumptive nominee, the delegate numbers are subject to change. It's non-binding.

And anyone who's betting against the Clinton machine in the conventions hasn't been watching. The Obama accusations (leaving aside whether they are true) are the first salvo in their campaign for as many delegates as possible out of the conventions.