Washington (CNN) Ken Cuccinelli is expected to be placed in the number two post at the Department of Homeland Security by Chad Wolf, the incoming acting Homeland Security Secretary, after legal hurdles prevented Cuccinelli from serving in the top role, according to a source familiar with the plan.

The Senate is set to vote on Wolf to become undersecretary for the Office of Strategy, Policy and Plans at the Department of Homeland Security Wednesday morning, clearing the way for him to become acting Homeland Security secretary

The expected move to elevate Cuccinelli, the acting US Citizenship and Immigration Services chief and an immigration hardliner, to a higher post within the department gives him greater latitude over President Donald Trump's signature issue. The decision to make him acting deputy DHS secretary is also indicative of how the White House views the Department of Homeland Security, which, despite its sprawling mission, has largely been tasked with executing Trump's immigration agenda.

The placement of Cuccinelli will likely mark a big change for the deputy position, which usually handles managerial tasks, while the secretary serves as the face of immigration. That dynamic may shift with the pairing of Cuccinelli and Wolf given Cuccinelli's bold approach to immigration.

David Pekoske, who served as acting Homeland Security Secretary Kevin McAleenan's number two, has been "clear that he fully intends" to serve out his five-year term as Transportation Security Administration administrator, according to a DHS official, and was not expected to stay on as acting Homeland Security deputy secretary.

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