First poll shows Thompson leading GOP field

A Rasmussen poll of likely Republican primary voters released Tuesday shows actor and former Sen. Fred Thompson (Tenn.) leading the GOP presidential field for the first time.

{mosads}Thompson, who has not officially announced that he is running but will likely do so next month, garnered 28 percent support, edging out former New York Mayor Rudy Giuliani, who was the choice of 27 percent of respondents.

In the past three weeks, Thompson’s numbers in the Rasmussen poll have soared. He was at 12 percent in a May 29 survey.

Former Massachusetts Gov. Mitt Romney and Sen. John McCain (Ariz.) each received 10 percent. It was McCain’s weakest showing to date in the Rasmussen survey.

The poll of 618 likely Republican primary voters has a margin of error of 4 percent.