Now that he has been elected president, one thing Barack Obama loses is his position in the U.S. Senate.

Article 1, Section 6 of the U.S. Constitution prevents an individual from holding more than one public office in the federal government of the United States. Matt Streb, assistant professor of political science, said that an individual who is the president and a member of Congress will have a conflict of interest.

“As a senator, he has to represent the state of Illinois. As president, he has to represent everyone,” Streb said. Streb added that there would be problems with the separation of powers. An individual serving as president and congressman would not only be able to vote to approve a war but be able to command the war effort as well.

Public administration professor Gerald Gabris said he expects Obama to deliver a formal letter of resignation to Gov. Rod Blagojevich. But the search for his replacement has already begun. The 17th Amendment gives the governor the power to appoint senators to a two-year shortened term.

According to a press release from the governor’s office, Blagojevich will “take his time and use a diverse senior staff made up of key members of his administration” to find a replacement.

A recent Chicago Tribune article discussed several possibilities for Obama’s replacement. Both Democratic U.S. Reps. Luis Gutierrez and Jesse Jackson Jr. have expressed interest in becoming the junior Illinois senator. Attorney General Lisa Madigan along with treasurer and Obama ally Alexi Giannoulias are also possible replacements.

“I have no idea how long [finding a replacement] will take,” Streb said. “But I’d be surprised if Obama doesn’t have a strong hand on who his replacement will be.”

There is speculation that Blagojevich would appoint himself to the position. However, Streb said he’d be surprised if this happened.