The Democrats and Republicans both have big money behind them. They can afford to sway public opinion, whether they are right or not.
Many people will be drawn to the group, there is sure to be at least one more that will crop up and have the same momentum. This will be for those who also know we need change but don't completely agree with the Tea Party. The fact is, it is all a distraction, the people who are paying the way for the current political parties will begin throwing money at which ever party looks to be taking the lead, some even pay both sides so they don't have to take any chances. All it takes is one individual to take bait, then we're in the same boat we are now.
Whether or not a grassroots movement can attract enough people isn't the real issue, but since you asked, my answer is yes. I just don't think it will make a difference even if they do. We have to remove the taproot to kill the weed, and to little is being done in an organized manor to accomplish that. We are divided, we are fighting each other, we keep taking the bait, so until we all come together, nothing will change.