They had been waiting for more than 24 hours, camped out on the pavements in a frigid Michigan chill. Stepping off her bus, in four-inch heels, black skirt and red blazer, came their heroine — clutching baby Trig. A roar went up, acclaiming the woman who they passionately believe is going to save America.

“Alaska and Michigan have so much in common — the huntin’, the fishin’ and the hockey mums!” she declared to chants of “Sarah! Sarah!” and “USA! USA!” She went on to pay homage to “just the hardworking patriotic Americans who are here”.

It was like 2008 had never ended. The first event of Sarah Palin’s 14-state, three-week, book-signing tour had all the trappings of a political campaign: veteran White House handlers, an advance team, a security detail, VIP invitations to local conservative activists . . . except this time, the former Alaska Governor is nobody’s running-mate.

Should anybody have doubts about what a potent political force Mrs Palin is — and what a formidable candidate she would pose if she chose to run in the next Republican presidential primary — attending this inaugural book signing in Grand Rapids, Michigan, would dispel them.

There were “I love Sarah Palin” T-shirts, “Palin Power” posters above moose heads, “Team Sarah” jumpers, children in pushchairs, octogenarians in wheelchairs and thousands of “Sarah Palin for President” badges.

They had been chanting “Sarah! Sarah!” since the first group of followers arrived at 9pm the previous night to start queuing up to meet her, and all had the same thing to say: she was “real”, the only Republican brave enough and tough enough to save America from the socialists running the White House.

Global warming was “horse****”, one man said. Another said that he was “sick of all these bull****” politicians — she’s the straight-shooter we need”.

These people were passionate about Mrs Palin, just like the hundreds of thousands who turned out to see her at rallies last year when she ignited the presidential race after being chosen by John McCain as his running-mate. Polls showed that she ultimately hurt the Republican ticket — a disastrous interview with CBS’s Katie Couric inflicted lasting damage — but since then her political brand has only become more potent.

It is a conservative, folksy mix of guns, God and small government that grassroots Republicans adore — especially at a time of exploding deficits and record federal spending.

“2012? What are the possibilities?” one reporter asked Mrs Palin as she worked the rope line to the country music anthem Only in America. “Not rulin’ it out. Not closin’ any doors,” she replied.

The book tour is an open slap to liberal America. It ignores big cities, concentrating on smaller ones, towns and some nearby military bases, in a series of swing states such as Ohio, Pennsylvania, Indiana, Florida and Iowa — the site of the first nominating contest in the next presidential primary.

Joe Verran, wearing a “Sarah Palin for President” T-shirt and a “Palin Power” baseball cap, replied: “You betcha,” when asked if he would like to see her in the White House. “She’s real. She is exactly what the American dream is all about. She has a son in the military. Everything about her life is what so many people in the world come to America to achieve.”

The title of her autobiography, Going Rogue, which was released on Tuesday but has been on top of the bestseller lists for weeks, derives from Mrs Palin’s public criticism during last year’s campaign of the McCain camp’s decision to abandon Michigan a month before the election.

Her dissent marked a turning point in her relationship with Mr McCain’s advisers. From that moment, they accused her of “going rogue” and a Republican civil war broke out.

She tries to settle many scores in the book, and has scathing criticism for two aides to Mr McCain in particular. They have called the book a work of fiction. Yet the renewed warfare has only convinced her supporters of the righteousness of her cause.

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