I disagree. If Clinton announces then I doubt she'll make it to Iowa. And if she does, she won't make it out of Iowa. The Democrats don't see the 2016 election as people voting out of their sincere desire for real change in the country. They see it as Clinton losing to Donald freakin' Trump. They won't forgive her for that.
That’s also a possible scenario. But we can hope that she’s successful enough to totally f@#$ everybody else up. That could also happen, and just in case it does, stock up on popcorn. She could also go 3rd Party out of spite. Whatever she does, it’ll be bad news for the Dems, unless she gets a stroke and dies.