Cantwell and the Public Option

At the July 9th rally, we presented a box of 291 pages of signatures collected by Moveon.org to Senator Cantwell's office. We wanted to get a clear statement of her position on the public health care option for the crowd and media gathered outside.

Her office presented us with a letter (dated July 9th) that was unambiguous in her support for a public option:

Let me be clear: a public option needs to be part of health care reform. I am pushing for a public option that will keep insurance companies honest by competing to drive down costs and improve quality nation-wide. This plan needs to be accountable to the people and must work to provide the best coverage for the best price.

I also received letter in the mail shortly afterward from the Senator dated one day earlier that says,

"An effective public option could help improve access to high quality health care....however, this will only be achieved if we take full advantage of our opportunity to overhaul America's health care system, instead of just expanding the flaws that exist in the current Medicare program."

Good news, right? The Senator pretty dramatically shifted her position from one day to the next.  Except that she has issued no press release to this effect, and news media are left guessing about her intentions.

Is the Senator saying one thing to protesters and another to the general public?  If so, why?