The former Tennessee senator gave Republican activists the red meat rhetoric they had been waiting for by lashing the liberal media, branding Democrats as elitists and holding up Senator John McCain's running mate, Mrs Palin, 44, as the beacon of ordinary American values.
“She is from a small town, with small town values, but that's not good enough for those folks who are attacking her and her family,” he said.
“Some Washington pundits and media big shots are in a frenzy over the selection of a woman who has actually governed rather than just talked a good game on the Sunday talk shows and hit the Washington cocktail circuit.
“Well, give me a tough Alaskan governor who has taken on the political establishment in the largest state in the Union - and won - over the Beltway business-as-usual crowd any day of the week.”
Republicans, incensed by the media coverage of the pregnancy of Mrs Palin’s daughter Bristol, 17, and claims that Mr McCain panicked into making an ill-judged choice without proper vetting, were delighted.
“The selection of Governor Palin has the other side and their friends in the media in a state of panic. She is a courageous, successful, reformer, who is not afraid to take on the establishment.”
During a comparison between Mr McCain and Mrs Palin, whom the McCain campaign has been portraying as a pair of maverick outsiders, he added: “Sound like anyone else we know?”
He sought to dampen criticism of her inexperience – she has been governor of the sparsely-populated state of Alaska for 20 months – by drawing an implicit contrast with Mr McCain’s Democratic opponent Barack Obama, who has not held executive office and has been a senator for less than four years.
“She has run a municipality and she has run a state. And I can say without fear of contradiction that she is the only nominee in the history of either party who knows how to properly field dress a moose ... with the possible exception of Teddy Roosevelt.”
Mr Thompson also mocked Mr Obama for giving “a teleprompter speech designed to appeal to American critics abroad”, a reference to his speech before 200,000 Germans in Berlin”.
He also poured scorn on Mr Obama’s slogans of “hope” and “change you can believe in”. Mr McCain, he said, had displayed “character you can believe in”. His experience as a Vietnam prisoner of war meant that “John McCain knows about hope”
He explained: “That's all he had to survive on. For propaganda purposes, his captors offered to let him go home. John McCain refused. He refused to leave ahead of men who'd been there longer. He refused to abandon his conscience and his honour, even for his freedom.”