The business of government lobbyists may be shaken significantly following a landmark Nigerian vote which saw the first democratic overthrow of a sitting government in the nation’s history.

According to OakTV, a new Nigerian government may review millions of dollars in contracts held by U.S. political lobbying firms.

In a report, the blog said that:

The change in leadership, from President Goodluck Jonathan to former military ruler Muhammadu Buhari, could be trouble for at least four firms with lucrative arrangements from the West African nation.

Levick, Squire Patton Boggs, Mercury and Weber Shandwick each have contracts worth a minimum of six figures per year with the Nigerian government.

“It’s not unusual for governments — whether foreign governments or even U.S. state or territorial governments — to switch lobbying firms after an election because the new government wants to have its own loyal troops in the field,” said Robert Kelner, the chairman of law and lobby firm Covington & Burling’s election and political law practice.

In total, the country spent about $4.41 million on lobbying and PR last year from U.S. firms, according to a review of forms filed with the Department of Justice (DOJ) under the Foreign Agent Registration Act.

The most recent contract — inked with Levick last June — resulted in more than $1.64 million in payments during the last six months of 2014, according to filings with the DOJ.

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