MIAMI — The Obama administration overturned a ban preventing a wealthy, politically connected Ecuadorean woman from entering the United States after her family gave tens of thousands of dollars to Democratic campaigns, according to finance records and government officials.

The woman, Estefanía Isaías, had been barred from coming to the United States after being caught fraudulently obtaining visas for her maids. But the ban was lifted at the request of the State Department under former Secretary of State Hillary Rodham Clinton so that Ms. Isaías could work for an Obama fund-raiser with close ties to the administration.

It was one of several favorable decisions the Obama administration made in recent years involving the Isaías family, which the government of Ecuador accuses of buying protection from Washington and living comfortably in Miami off the profits of a looted bank in Ecuador.

The family, which has been investigated by federal law enforcement agencies on suspicion of money laundering and immigration fraud, has made hundreds of thousands of dollars in contributions to American political campaigns in recent years. During that time, it has repeatedly received favorable treatment from the highest levels of the American government, including from New Jersey’s senior senator and the State Department.