Mitt Romney, the front-runner in the Republican presidential race, reportedly invested millions in the Cayman Islands, according to ABC news.

It is estimated that Romney’s fortune amounts to around $250 million, and on Tuesday he revealed that he pays 15 percent on his taxes, much lower than many Americans.

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The ABC report, based on securities records and documents from Bain Capital, states that Romney has $8 million invested in at least 12 funds in the Cayman Islands, and Bain Capital, formerly run by Romney, has control over “138 secretive offshore funds in the Caymans.”

The latest polls suggest Romney’s lead since New Hampshire has been halved, attributed to criticism of his ties with Bain Capital, and his continued reluctance in releasing his tax returns.

A new Time CNN/ORC poll shows Newt Gingrich gaining ground in South Carolina at 23 percent, though Romney is still in the lead with 33 percent of the vote, according to The New York Times.

Gingrich, speaking to a crowd of supporters today, said, “I fully expect the Romney campaign to be unendingly dirty and dishonest for the next days because they are desperate,” reported The Times.

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Romney, at a stump speech in South Carolina today, shot back, “My goodness I listened to speaker Gingrich the other night talking about the enterprises I’ve been associated with. I’m proud of the fact that I worked in the private sector, that I’ve achieved success,” reported The Boston Herald.

This post originally appeared at GlobalPost