Ms Biden Owens, a close confidante and life-long campaign manager of her brother, said the Duchess of Sussex would be “welcomed” into her party and would “of course” make a good candidate for the top job.
“It’s wonderful to have women in politics,” the 76-year-old told ITV’s Good Morning Britain.
“The more women we have, the better our democratic system will work. A better point of view, a different point of view.
“We embrace all women and we welcome her to come in and join the Democratic party.”
When asked if Meghan would make a good candidate for the top job, Ms Biden Owens said: “Yes, perhaps. Of course she will.”
Although she has never publicly expressed a wish to run for president since marrying into the British royal family, the idea of Meghan running for the US presidency is not far-fetched.
She has held high-level meetings with the governors of California and New York, called for “vaccine equity” at the Global Citizen Live concert in Central Park and telephoned Republican senators out of the blue to press her case for paid parental leave being signed into US law.
Tom Bower, who is currently working on an unauthorised biography of Meghan, told Closer magazine: “The prospect of Meghan running for president is possible and I’d even say likely. I really believe it’s where she sees herself going.”
Omid Scobie, the co-author of the book Finding Freedom, the biography that Meghan did co-operate with, said: “Meghan is the embodiment of the American dream. One day we may see Meghan become president.”
In 2020, one unnamed friend told Vanity Fair that “one of the reasons she was so keen not to give up her American citizenship was so she had the option to go into politics”.
Meghan “would seriously consider running for president”, they added.
If she does want to run for president as a Democrat, it would be unlikely to happen in 2024.
Ms Biden Owens, who was a senior adviser to her brother’s successful 2020 presidential campaign, said she “absolutely” expects him to run again in less than three years.
He will be just two weeks shy of his 82nd birthday when Americans go to the polls on November 5, but his sister said: “Joe is the right person at the right time for the right job. And there are lots of things still to do.”
Ms Biden Owens has long been a staunch defender of her brother, and has rejected claims he is gaffe prone.
Riffing off the cuff during a speech in Warsaw at the end of March, the president caused a diplomatic incident by saying Russian president Vladimir Putin “cannot remain in power”.
The White House was quick to clarify: “The President’s point was that Putin cannot be allowed to exercise power over his neighbours or the region.
“He was not discussing Putin’s power in Russia, or regime change.”
Telegraph Media Group Limited