Word at the weekend that Sarah Palin has been let go by Fox News, where she had been peddling her conservative positions for the past three years, barely shocked. Who hadn't seen that coming? Yet it is also highly telling. The Republican Party is rushing to rebrand itself and whose face does it not want on its new packaging? Sarah Palin's.

The former Governor of Alaska reportedly cost the Rupert Murdoch-owned network $1m a year. That worked out last year at about $16 (£10) a word, a lot for someone who was number two on a failed presidential ticket more than four years ago (or a lot for anyone, for that matter). Her appearances, most by way of a satellite link to a studio that Fox had installed in her home in Wasilla, had become less frequent. She drew attention to the fact when she posted a Facebook message during the Republican convention last August whining that Fox wasn't coming to her for commentary.

But Ms Palin's peak probably came not when she was running alongside John McCain (possibly the worst decision of his political life) but in 2010, when the Republican Party was all about the Tea Party surge. Crowned as its figurehead, she wrote blockbuster books and had television shows, all the while keeping herself politically relevant on Fox.

But that angry energy has ebbed. A poll by Rasmussen says 8 per cent of voters describe themselves as Tea Party members, down from 24 per cent in 2010. Only 30 per cent have a positive view of it. "Sarah Palin represented a time and place… and that time is passing very quickly and party leaders are finally understanding that," Joe Scarborough, the MSNBC news anchor and former Republican Congressman, noted yesterday.

They may also have concluded that more than irrelevant, Ms Palin is toxic. The reinvention going on now in the wake of Mitt Romney's defeat is about rediscovering moderation, abandoning radical stances adopted notably by the Tea Party. It is why party leaders have put off a fight with President Barack Obama on the debt ceiling until the early summer. It's also why four Republican US Senators, led by Mr McCain, appeared alongside four Democrat colleagues yesterday to lay out a plan for comprehensive immigration reform that will include offering a path to green-card status for the 11 million illegal aliens in the country.

Just a few months ago, such a development would have been anathema to nearly everyone in the party. Mr Obama, who will lay out his own version of reform in Las Vegas this morning, now has a chance in his second term to sign into law a deal on remaking the country's byzantine immigration rules that has eluded his predecessors.

The Republicans are doing it because of the drubbing suffered by Mr Romney among Hispanic voters last year. No one blinked a year ago when the primary candidates vied with one another for the most extreme stance on immigration, whether it was building more walls on the borders or making the lives of those already in the country illegally so miserable that they would, as Mr Romney put it, "self-deport". Now, those statements make their eyes water. This month, Ms Palin was excoriated by Colin Powell, the former general and Secretary of State, for accusing Mr Obama last year of "shuckin' and jivin'" on what happened at the US consulate in Benghazi. It was a racist slur from the slavery age, he said. In the same interview he spoke of a "dark vein of intolerance in some parts of the party", adding: "What I mean by that is they still sort of look down on minorities."

Ms Palin may have consigned herself to eventual oblivion in early 2011, when some sought to implicate her in the attempted assassination of Congresswoman Gabrielle Giffords in her Tucson constituency. A Palin website in 2010 had sought to highlight Ms Giffords's district as winnable with a graphic featuring cross-hairs. The former Governor posted a video on Facebook accusing the liberal media of committing "blood libel" against her. The phrase has well-known anti-Semitic connotations. She was flayed for it. Earlier this month, the Governor of Louisiana, Bobby Jindal, said the Republicans had to "stop being the stupid party" if it is to win again. He was referring most obviously to the most embarrassing incident of 2012 when Todd Akin, a Senate candidate in Missouri, said women who were victims of "legitimate rape" had some biological means to stop becoming pregnant. Would he put Ms Palin, utterer of "blood libel" and "you betcha", in the same stupid box?

Ms Palin at the weekend said leaving Fox was an opportunity for her. "We can't just preach to the choir; the message of liberty and true hope must be understood by a larger audience," she said. Everyone would wish her luck with that, except perhaps for those now engaged in making the Republican Party more broadly palatable again.

Quest for success: Tea Party members

Ron Paul

Once dubbed the Tea Party's "intellectual godfather", the 77-year-old staunch libertarian retired from politics after failing to secure the Republican presidential nomination last year. His son Rand, the junior Kentucky Senator, remains a member.

Michele Bachmann

The Minnesota Congresswoman was a founder of the Tea Party Congressional Caucus. She was moved to the House Permanent Select Committee on Intelligence this month – an important role for her, and that of the Tea Party.

Jim DeMint

The former South Carolina Senator resigned last month and said he would lead the Heritage Foundation, the conservative think tank, adding: "The election taught conservatives we can no longer entrust political parties to carry our message."

Dick Armey

Once seen as the de facto national Tea Party leader, the 72-year-old has recently helped to reinforce Louisiana Governor Bobby Jindal's assertion that the Republican Party is now seen as the "stupid party", through a series of gaffes.