The letter, posted online by the Institute for Women's Policy Research, a think tank devoted to women's issues, is still gathering signatures but has already attracted support from some recognizable names in Washington.
Names on the letter include Alice Rivlin, a senior fellow at the Brookings Institution who headed the Office of Management and Budget under President Clinton, and Christina Romer, a former economic adviser to President Obama who has been a vocal Yellen advocate.
The letter makes no mention of Yellen's top competitor for the job, Larry Summers, although several of the points addressed in the letter appear to highlight perceived concerns about how Summers would lead the central bank.
The letter argues Yellen has exhibited "consistently good judgment" and was one of the first to identify the dangers in the financial sector before the collapse in 2008. It also says Yellen is "willing to hear multiple points of view," an apparent jab at the perception that Summers's strong personality and claims he can ruffle feathers among colleagues.
"There is less and less room in modern public policymaking … for a single leave to dominate discussion," the letter stated.
Summers is reportedly the front-runner for the job, having worked closely with Obama as an economic adviser. The president has defended Summers both in public and in private to Democratic colleagues in Congress but has insisted he has not settled on a nominee yet.
Obama's pick is expected to come sometime this fall, before Fed Chairman Ben Bernanke wraps up his second term at the beginning of 2014.
Several groups, particularly on the left, have taken the rare step of openly advocating for Yellen over Summers. Senate and House Democrats have penned letters backing Yellen, and the AFL-CIO has also said they would prefer her over Summers.
But it remains an open question whether that preference could amount to opposition for Summers if he ends up being the nominee.