Biden said he had received a letter from an Indian Biden after becoming a senator in 1972, suggesting they could be related
Already bursting with pride at Kamala Harris's ancestry, India has now started digging up potential local roots for US President-elect Joe Biden.
The next leader of the United States has speculated that he might have had relatives in colonial India. While there is no proof, the Biden name has become a genealogical target of investigation across the country.
A plaque commemorating 19th-century British ship captain Christopher Biden has been a popular selfie spot in the eastern city of Chennai since the US election.
And a Biden family in western India says it has become "exhausted" by calls since their namesake staked his claim to the White House.
The American vote has been under the spotlight in India because Biden's running mate is the daughter of a migrant from Tamil Nadu state.
The 56-year-old Harris has made much of her Indian connections and how she likes to eat "idli with a really good sambar" -- typical food from the south.
Less attention has been paid to Biden, who has established Irish links. But he spoke of possible Indian connections on a trip to Mumbai in 2013 when he was vice president.
Biden said in a speech that he had received a letter from an Indian Biden after becoming a senator in 1972, suggesting they could be related.
"One of the first letters I received and I regret I never followed up on it," he said.
Mumbai Bidens lie low
The letter said their "mutual, great, great, great, something or other worked for the East India Trading Company back in the 1700s."
It sparked excitement in Chennai, capital of Tamil Nadu state, which is also home to Harris's Indian relatives.
A plaque at St George's Cathedral in Chennai that celebrates Christopher Biden, born in 1789, has suddenly become a local tourist draw.
"We've come to know the records of two Bidens -- William Biden and Christopher Biden -- who were brothers and became captains of the East India Company on merchant ships in the 19th century," the Bishop of Madras, Reverend J George Stephen, told AFP.
"While William Biden died at an early age, Christopher Biden went on to captain several ships, and eventually settled down in Madras," which is now known as Chennai.
Despite the speculation, there has been no confirmation that the Biden brothers are related to the 77-year-old American.
If the president-elect does have an Indian ancestor, Christopher is considered the most likely candidate, according to experts who have studied family records.
There are also Bidens in Mumbai and Nagpur in Maharashtra state who could be descendants of Christopher, one of eight children of a John Biden who could be the common link.
The media attention has been overwhelming, according to the Maharashtra Bidens. Indian media has speculated that their late grandfather Leslie wrote to the US politician.
Rowena Biden, a family member in Mumbai, insisted that they were not trying to establish any relationship.
"We wish Mr Joe Biden all the best for his new role as president of the USA but we are not trying to establish any connections or linkages," she told AFP.
"We share a last name and that's about it," she said.
"All of us are well-to-do financially and have well-settled lives so we don't need any gains -- monetary or non-monetary."
Rowena Biden said that after the first reports came out about the possible links, "people started tracking us to our house and everyone in the family had to bear the brunt of it."
The "undue limelight" had cast a shadow over "the primacy of Mr Biden's win and our privacy as well," she said.