Well-wishers have donated tens of thousands of dollars to an elderly man photographed while selling kindling by the roadside to pay for his wife’s medical bills.

Mississippi resident Jessica Pittman took to Facebook last week to describe the plight of 80-year-old recent widower Kenneth Smith, encouraging readers to pay him a visit.

"If y'all need any kindling wood please come buy from this precious 80-year-old elderly man,” Miss Pittman wrote.

"He is there every day for hours. Selling for $5 a bag.”

Ms Pittman said she remembers seeing Mr Smith selling kindling at the same location a year prior with his wife Helen, raising money to pay for cancer-related medical bills.

She said Mr Smith’s wife died a few weeks ago and that the grieving pensioner is still working to cover those expenses.

"My heart breaks every time I pass him. He waves at every single car that passes,” Ms Pittman wrote.

"Friday I was at the stop sign as a funeral procession was passing by. And he was standing alert, with his straw hat over his heart."

Ms Pittman’s post has received thousands of reactions and shares.

Stepson Leslie Smith has since launched an online campaign to raise funds for his stepfather.

Mr Smith Jnr explains Mr Smith Snr's life savings have been completely exhausted by his wife’s battle with cancer.

The campaign has received a staggering US$105,568 (A$142,496) worth of donations already from supporters across the US and the world.

A woman who appears to be Mr Smith Snr’s daughter has since commented on the page, describing his reaction to public support.

"My dad just came by and he is as nervous as a cat on a hot tin roof,” she wrote.

"He said he 'hoped people did not think he was begging for money’.

"I told him people thought he was inspiring.

"Thanks so much for the donations, your outpouring of love is what I find truly inspiring.”