The Clinton team had been quiet about Stein's crusade, but campaign lawyer Marc Elias said that because a recount was set into motion Friday — and could begin as soon as next week — they want to see a "fair" process for all involved.
"Because we had not uncovered any actionable evidence of hacking or outside attempts to alter the voting technology, we had not planned to exercise this option ourselves," Elias wrote in a Medium post on Saturday explaining the decision, "but now that a recount has been initiated in Wisconsin, we intend to participate in order to ensure the process proceeds in a manner that is fair to all sides."
Wisconsin election officials said they received Stein's paperwork and that they were still waiting to obtain a cost estimate from county clerks to calculate a fee that Stein's campaign must pay before the start of the recount.
The Green Party's presidential nominee also has plans to file a recount effort in Michigan, where NBC News has yet to officially call a winner, and Pennsylvania.
President-elect Donald Trump still holds narrow leads in all three states, and his victories in Pennsylvania and Wisconsin provided him with the Electoral College advantage he needed to win the presidency.
Elias acknowledged that the "the number of votes separating Donald Trump and Hillary Clinton in the closest of these states — Michigan — well exceeds the largest margin ever overcome in a recount," but said they felt it was "important, on principle" to partake in and monitor the process.
If Stein follows through with her promise to pay for recounts in Michigan and Pennsylvania, Elias wrote, the campaign will "take the same approach" with additional states and participate in any verification efforts there.
Until now, the Clinton campaign declined to comment on the potential re-tallying. After what aides called a crushing and unanimously stunning loss, most went silent as they came to grips with the outcome.
Over the last few weeks, lawyers and data scientists urged the campaign to consider a recount, according to Elias' post. He also said a deciding factor for the campaign was Russia's reported interference in the U.S. election process.
Besides "quietly" taking steps to "rule in or out any possibility of outside interference," the campaign also dispatched resources to critical battleground states.
"We have monitored and staffed the post-election canvasses — where voting machine tapes are compared to poll-books, provisional ballots are resolved, and all of the math is double checked from election night," he wrote.
Elias also acknowledged the anguish that many of Clinton's supporters and staffers felt after the shocking upset.
"We certainly understand the heartbreak felt by so many who worked so hard to elect Hillary Clinton, and it is a fundamental principle of our democracy to ensure that every vote is properly counted," he wrote.