Sarah Palin’s eccentric speech to a Republican conference in Iowa last weekend, which has been criticised even by some of her conservative supporters, has now helped a group backing Hillary Clinton to raise $50,000, a spokesman said on Thursday.

Ready For Hillary, the political action committee (PAC) collecting money and support in anticipation of a second presidential campaign by Clinton, used Palin’s speech to the Freedom Summit to fuel a fundraising drive after she mocked the former secretary of state.

Waving a “Ready For Hillary” car magnet as she stood behind the podium at a theatre in Des Moines, Palin said: “Hey Iowa, can anyone stop Hillary? To borrow a phrase, ‘Yes we can!’ And it starts here and it starts now.”

Palin, the 2008 Republican vice-presidential nominee and former Alaska governor, also appeared to make a jibe about Clinton’s age. “Is Hillary a New Democrat,” she said, referring to the party’s 1990s centrist faction, “or an old one?”

Clinton is 67.

Ready For Hillary promptly drew attention to the speech in an email to supporters. “Palin was trying to say that Republicans will be ready to launch relentless attacks on Hillary from the moment she announces her decision,” it said. The group asked for donations of $20.16 to help counter the Republican effort, offering car magnets in return.

The group told supporters on Tuesday that Palin’s speech had brought in more than $25,000 in contributions. “The response we got was overwhelming – hundreds of supporters stepped up,” a spokesman said in an email, joking that the total meant Palin qualified as a co-chair of the group’s national finance council.

However, Seth Bringman, a spokesman for Ready For Hillary, said in an email to the Guardian on Thursday that the total haul of contributions directly prompted by the email about Palin’s speech now actually stands at “over $50,000”.

Ready For Hillary has raised about $12.2m since its formation, according to the Center for Responsive Politics.

Palin’s speech, in which she described President Barack Obama as an “overgrown little boy who is acting kinda spoiled”, received poor reviews from several conservative commentators, while Republican operatives cast doubt on her latest claim to be considering a presidential campaign of her own.

Former colleagues on Fox News, where Palin once worked as a political analyst, appeared to join the ranks of those puzzled by her remarks. Sean Hannity, typically a loyal supporter, noted to Palin that “a lot of people” had been critical. “Did the teleprompter go down, did you have trouble with the copy, was there any moment in the speech where you had any difficulty?” Hannity asked.

Palin was also engaged in an unlikely dispute with Bill O’Reilly, the conservative broadcaster and author who is frequently the channel’s top-rated anchor. After O’Reilly appeared to mock her as a mere reality television personality, Palin returned to Hannity’s show to complain. “The left doesn’t do that, OK?” she said. “They take this serious, because this is war.”

O’Reilly defended his remarks during his show on Wednesday. He said that Palin and Donald Trump, the television host and property tycoon who has also claimed to be considering a presidential campaign, were “very high-profile folks, and both have starred in reality TV shows.” O’Reilly added: “It was perfectly in context and harmless.”