This Thanksgiving, it appears many people are thankful for Hillary Clinton - and she herself could have a great reason to celebration as calls for an election recount gather steam.

Clinton appeared in great spirits as she was was spotted shopping for Thanksgiving supplies at a supermarket in Chappaqua, where she and husband Bill have a home, by a number of fans on Wednesday.

The 69-year-old happily took selfies with a number of women who approached her as she shopped.

And on Thursday, she took to Twitter to share a picture of the many messages of thanks left at the end of her street for her.

Alongside the picture, she wrote: 'I was greeted by this heartwarming display on the corner of my street today. Thank you to all of you who did this. Happy Thanksgiving.'

It comes as Dr Jill Stein managed to raise more than $3.5 million in a day - enough to fund recounts in Wisconsin, Michigan and Pennsylvania - after experts said it was possible that hackers had artificially lowered Clinton's counts there.

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Hillary Clinton shared a picture of the messages of thanks left on the street of her her home in Chappaqua, New York, where she and her family are spending Thanksgiving

Hillary Clinton spotted shopping for Thanksgiving supplies at a supermarket in Chappaqua, by a number of fans on Wednesday

Meanwhile, Brittany Valente shared a picture with the former Secretary of State after bumping into her with her husband and grandson Aiden.

'Ran into Hill and Bill at the local market. Met their grandson Aiden, cutest little guy ever. #hillaryclinton,' Valente captioned the image on Instagram.

Bill was 'busy looking at cheese' while his wife took pictures with everyone who asked for one, Valente said.

'They were so relaxed and shopping for Thanksgiving dinner at the local village market,' she told NBC News.

'They were so nice talking to everyone, wishing them happy holidays and at one point Hillary said 'We must stay strong together no matter what. Thank you for your support.''

'When you go pick up your pie and the entire Clinton family is shopping 2,' wrote Linda Bosco on Twitter alongside a picture with the Democratic candidate for president.

'She was very happy, relaxed-looking. She was with Bill, Chelsea, Marc, and her two grandchildren,' Bosco, who also lives in Chappaqua, told The Telegraph.

'The store was crowded with people picking up their Thanksgiving orders.

'She was very cordial, talking to people and taking a few photos, but was concentrating on her grandchildren as the store got more crowded.'

Brittany Valente shared this picture with the former Secretary of State after bumping into her with her husband and grandson Aiden

'When you go pick up your pie and the entire Clinton family is shopping 2,' wrote Linda Bosco (above) on Twitter alongside a picture with the Democratic candidate for president

The deadlines for petitioning for a recount in all three states are in the coming days, with Wisconsin's on Friday.

Dr Stein, the Green Party candidate, announced a fundraising effort on Wednesday to pay for such recounts. She surpassed her $2million target in hours.

Meanwhile, a group of election lawyers and data experts has asked Clinton's campaign to call for a recount of the vote totals in the three battleground states - to ensure that a cyberattack was not committed to manipulate the totals.

There is no evidence that the results were hacked or that electronic voting machines were compromised. The Clinton campaign on Wednesday did not respond to a request for comment as to whether it would petition for a recount before the three states' fast-approaching deadlines to ask for one.

President-elect Donald Trump won Wisconsin and Pennsylvania by razor-thin margins and has a small lead in Michigan. But all three states had been reliably Democratic in recent presidential elections.

The group, led by voting-rights attorney John Bonifaz and J. Alex Halderman, the director of the University of Michigan Center for Computer Security and Society, contacted the Clinton campaign this week.

Dr Stein, the Green Party candidate, announced a fundraising effort on Wednesday

Dr Stein surpassed her $2million target in hours and has raised more than $3.5million by Thursday morning

That call, which was first reported by New York Magazine, raised the possibility that Clinton may have received fewer votes than expected in some counties that rely on electronic voting machines.

But Halderman, in an article posted on Medium on Wednesday, stressed that the group has no evidence of a cyberattack or voting irregularities.

He urged that a recount be ordered just to eliminate the possibility.

'The only way to know whether a cyberattack changed the result is to closely examine the available physical evidence - paper ballots and voting equipment in critical states like Wisconsin, Michigan and Pennsylvania,' Halderman wrote.

Recounts, which are often costly and time-intensive efforts, would likely only be initiated if the Clinton camp pushed for one, though Wisconsin independently announced that it would conduct an audit of its vote.

A call for a recount, particularly coming on the heels of a fiercely contested and sharply partisan election, would likely be cheered by Democrats but denounced by Republicans eager to focus on governing.

A request to the Trump transition team for comment was not immediately returned.

Computer experts used a statistical analysis to conclude Clinton did worse in states with electronic voting machines - which they argue could have left the door open to hacking

Trump's campaign had long believed that his message of economic populism would resonate in the Rust Belt.

He frequently campaigned in Pennsylvania and made a late push in both Wisconsin and Michigan, successfully turning out white working-class voters whom pollsters may have missed.

Many pre-election polls showed Clinton with slight leads. While advocating for the recounts, Halderman writes that 'the most likely explanation' for Trump's surprise win 'is that the polls were systematically wrong.'

The focal point of any possible electoral cyberattack presumably would have been electronic voting machines that, whether or not they are connected to the internet, could be infected with malware that could change vote totals.

But many of those machines produce a paper record of the vote that could be checked to see if the vote tabulations are accurate.

Pennsylvania is considered one of the states most susceptible to hacking because 96 percent of its voting machines have no paper trail.

Margot Gerster shared a picture with Clinton after she bumped into her and Bill walking their dog near their Chappaqua home the day after Election Day

Wisconsin is far less vulnerable because it uses electronic machines with voter-verifiable paper trails in most counties. Michigan is considered the safest of the three because it uses paper ballots.

Officials in the three states confirmed that no recounts have been ordered.

A spokesman for the U.S. Justice Department says it is not tallying the number of voting complaints to determine whether federal action is warranted.

Many election experts have called for routine post-election audits designed to boost public confidence in vote outcomes, by guarding against both tampering and natural vote-counting mistakes.

These could involve spot-checks of the voting records and ballots, typically in randomly selected precincts, to make sure that votes were accurately recorded.

In many states, audits involve hand-counting the votes on paper ballots and comparing the results to the totals stored in the state's electronic voting system.

Such audits do sometimes turn up mistakes that reverse an election. That happened in Florida's Palm Beach County in 2012, when a post-election audit determined that the 'winners' in two city council races were actually losers.

President-elect Donald Trump won Wisconsin and Pennsylvania by razor-thin margins and has a small lead in Michigan. Above, Clinton is pictured on November 16

Routine audits also make it possible to confirm the accuracy of elections without putting the onus on losing candidates to call for a recount.

In states without regular audits, a candidate who questions the results gets 'painted as a sore loser,' Pamela Smith, president of the nonprofit Verified Voting, said in an interview earlier this year.

'If you do a regular audit, you often don't need a recount. It either shows the count was right or you find something.'

Any attempted hack to swing the results in three states would have been a massive and unprecedented undertaking.

But electoral security was an issue that loomed large in many Americans' minds this year as the Democratic National Committee and several Clinton staffers had their emails breached and later released.