Sen. Arlen Specter (Pa.) had received refund requests from 15 contributors as of the close of business Wednesday, according to his campaign. The recent Democratic convert has said he will honor those requests in wake of his party switch earlier this week.Until this week, Specter has consistently said he planned to run for re-election as a Republican in 2010. Specter said he switched parties because polling showed he could not defeat former Rep. Pat Toomey in the GOP primary. Specter raised almost $1.3 million in the first quarter of this year, adding to his $6.7 million campaign war chest. And now that he’s switched to the other side of the aisle, several of the Senator’s former donors want their money back. Businessman Chris Hackett (R), who lost a challenge to Rep. Christopher Carney (D) in Pennsylvania’s 10th district in 2008, hosted a fundraiser for Specter several weeks ago in Wilkes-Barre. Hackett also personally ponied up $4,800 for Specter, all of which he said he plans to ask the Senator to refund. “It puts me in a very difficult position, particularly if you look at it from a background of how much support Pat Toomey and the Club for Growth gave me both in the primary and in the general election,— Hackett said.