Washington -- Former Sen. Fred Thompson of Tennessee is about to take a big step toward a formal presidential campaign, a move that will shake up the unsettled Republican field and throw a wild card into the competition for the GOP's conservative core.
This week, Thompson asked supporters to begin collecting campaign donations on June 4, after he files papers with the Federal Election Commission to establish a political committee to "test the waters" for a White House bid.
The move is the clearest signal to date that Thompson, best-known for playing a gruff district attorney on Law & Order, is shelving his reluctance to join the race. He has been urged by friends and conservatives to run and fill a perceived void on the right flank of the Republican candidate field.
After weighing a bid for months, Thompson announced in a Tuesday conference call with about 75 potential donors that he was about to establish his formal fundraising committee, Friends of Fred Thompson. Donors listening in on the call, dubbed the "first-day founders," were encouraged to raise about $50,000 each.
Thompson has been keeping a high profile in conservative circles and preparing behind the scenes to launch a campaign. He has gathered a cadre of senior advisers that includes Ken Rietz, a former political director of the Republican National Committee; and Michael Toner, former chairman of the FEC.
On Saturday, he will speak at a major Republican Party event in Virginia known as the Commonwealth Gala. He addressed a conservative group in Orange County, Calif., in early May, but his speech was panned by some conservative commentators as lackluster.