Kucinich is not a Republican.  If this bill had everything he wanted in it, he would (in my prediction) vote Yes in a heartbeat.  If the bill had even 40% of what he wanted, he would still probably vote Yes.

Kucinich's legacy can only be hurt by his voting No for a bill that had "everything he wanted."  He would be known as the stalwart Liberal in Congress who helped kill a great bill which would have realized a major plank in his agenda.  An enormous "lose" as judged by (Democratic) history.  The Republican Party's self-identified legacy here is in causing the failure of Obama's Presidency.  So Grassley and Snowe _help_ their legacy as Republicans by blocking this bill at all costs.  If it fails, and a Republican is elected, and this turns the tide of the country toward appreciation of Republican governance, that is a huge "win" as judged by (Republican) history. 

If Kuninich wanted his 15 minutes as he killed a Single Payer bill, he'd have to be aware that he was seeking this fame in direct opposition to his political foundation.