Via the Washington Post:
Scott Walker is making an early push to stockpile money for his likely presidential bid, asking donors to raise $27,000 by mid-July, when he is expected to launch a White House campaign. An e-mail that went out to supporters Thursday asked them to be the first donors to a new “testing the waters” committee, which he can use to raise and spend money as he considers a run. All contributions made to the committee now would go to his eventual campaign. Donors were urged to visit a new Web site and participate in “The Race to 270” by raising $27,000 by Sunday, July 12. That is the day before when supporters expect Walker to formally launch his campaign in the Milwaukee area.
As of now there are twelve officially declared GOP candidates.