None that I can think of, and neither can The Atlantic.
I don’t know about Jesse Ventura, but I find Schwarzenegger and Sonny Bono’s pre-political careers as self-made showbiz entrepreneurs – to say nothing of Jon Corzine’s career in finance – much more impressive than anything Caroline Kennedy has ever done. Her life has been dedicated to worthy pursuits, by and large, but most of her accomplishments (fundraising for New York public schools, editing essay collections in honor of her father, etc.) are classic “born on third base” endeavors – laudable enough without being terribly impressive. And all of the names on Marcus’s list actually submitted themselves to the democratic process on their way to the Senate, the House, and the California’s Governor’s Mansion; for an appointment to fill a vacant seat (especially a safe vacant seat), the bar ought to be set a bit higher than “she’s more qualified than Sonny Bono.”
Here’s a more provocative way of thinking about it. Caroline Kennedy is no doubt more prepared – in terms of her base of knowledge about national politics, her comfort with the ways of Washington, etc. – to be a United States Senator than Sarah Palin was to be Vice President. But if you consider where the two women started and stack their subsequent accomplishments against one another, Palin’s Alaskan career is roughly six times more impressive than Kennedy’s years as a high-minded Manhattan socialite and custodian of her family’s good name. That doesn’t mean that McCain was wise to pick Palin as his running mate. But if you think he wasn’t, then you should definitely hope that the Democratic Party of New York hunts a little longer through its ranks before handing a Senate seat to the editor of The Best-Loved Poems of Jacqueline Kennedy Onassis.