Well...
No idea when this entry was made, so "...the past year or so, she changed her registration to Democrat." is ambiguous. Assuming that the entry was made recently, this puts the timing about right to give support to the claim she made.
This is the bit of nastiness that Heinz-Kerry responded to?
Or this? Also, maybe this is the sensitivity to criticism that you refer to (charge of treason thrown in for free!)? [pertinent text is all the way at bottom; or find on: "WSJ whitewashes attacks on Cleland"]
Doesn't sound to me like telling her what to say does much good.
Go ahead and run her through the Republican mud-machine, if you like. I think she can take it.