Republicans have blasted Clinton over the controversy, such as Representative Trey Gowdy, a House Republican leading an investigation of how the former secretary of state handled the 2012 attack on the US consulate in Benghazi, Libya, in which US Ambassador Christopher Stevens and three other Americans were killed.

Gowdy took to the airwaves Sunday on the CBS' "Face the Nation" to blast Clinton over the email scandal.

Senate Majority Leader Mitch McConnell of the Republican Party also expressed concerns over the email account's security. Former Florida Governor Jeb Bush, a Republican front-runner for the 2016 presidential race, said Clinton's decision to use a personal server is "baffling."

"Republicans are complaining about her not following the administration's rules because it helps them argue that she fell short in a variety of ways as Secretary of State," West said.

Indeed, foreign policy is expected to be a major issue in 2016, and that may spell trouble for Hillary Clinton, as critics will view the likely candidate as tainted by the White House's perceived foreign policy missteps on such issues as the Islamic State, which has overrun vast swaths of territory in the Middle East and threatened to attack the United States.

"(Republicans) want to argue that she has a poor record of foreign policy and that many of the criticisms about (US President) Obama also apply to her," West said.

A number of presidential candidates see foreign policy as a great issue for the Republican Party because of all the chaos and uncertainty that exist around the world, he added.