The Green Party presidential candidate, Jill Stein, petitioned on Friday for a recount in Wisconsin, one of the states that put US president-elect Donald Trump over the top in his surprise election victory.
Wisconsin Elections Commission administrator Michael Haas says Ms Stein met Friday's deadline to submit documents for a recount.
"The commission is preparing to move forward with a state-wide recount of votes for president of the United States," Mr Haas said.
Ms Stein received about 30,000 votes in Wisconsin, or 1 percent of the 3 million cast in the state.
Ms Stein's campaign is seeking to overturn the results in Wisconsin, Pennsylvania and Michigan, all states where Democratic nominee Hillary Clinton was expected to win but lost to Mr Trump.
Flipping the three states from Mr Trump to Ms Clinton would swing enough electoral votes to change the outcome of the election.
Finding enough problems to change the presidential result in three states is considered highly improbable.
Ms Clinton won the national popular vote by about 2 million votes but unexpectedly lost in the decisive Electoral College, in which states are weighted by population.
"We are raising money to demand recounts in Wisconsin, Michigan, and Pennsylvania - three states where there is a significant need to verify machine-counted vote totals," the Stein campaign said.