Above is the trending graph of potential GOP candidates from the aggregate at Real Clear Politics. The green line represents Sarah Palin's polling movement over the past few months ( Romney is the purple line). Significant factors would be Huckabee Daniels and Barbour announcing they were not running and the commencement of Palin's bus tour. The tour might have signalled to potential Palin supporters that she will indeed be a candidate and thus made them more certain that indication her as a preference was not a wasted indication.
If we look at the actual polling results for May, or the latest available from any one firm, and compare them to those from June too date, the reason for the trend lines striking upturn is very clear-and this is without Palin having as yet made a definite commitment to running. PPP Polling most recent result was in April and Reuters does not have a previous relevant Palin history on RCP.
Polling Firm Month Polled Month Polled
CNN May 13% June 20%
GALLUP May 15 June 16
FOXNEWS April 9 June 12
ABCWASHPO April 5 June 17
REUTERS N/A June 19
QUINNIPIAC April 15 May 15
PPP April 8 May 16.5 (aggregate)
Aggregate +5.67 (+52%) 10.83 16.50