The chief of staff to the Senate Foreign Relations Committee, Tony Blinken, is accompanying Barack Obama on his high-profile trip to Afghanistan and Iraq.

Blinken is chairman Joe Biden's right-hand man on the Foreign Relations Committee and considered his closest adviser.

Biden, a Delaware Democrat, has often been mentioned as a possible running mate with Obama and the presence of his top committee staffer and long-time friend and adviser is sure to further speculation about an emerging Obama-Biden relationship.

Elizabeth Alexander, a committee spokeswoman, described Blinken's role as standard operating procedure.

"Tony is traveling in his capacity as staff director of the Senate Foreign Relations Committee," Alexander said. "Two of the three 3 senators (on the trip) are on the committee and there is precedent for committee staff traveling with members other than the chairman."

Obama is traveling with Sens. Jack Reed, D-Rhode Island, and Chuck Hagel, R-Nebraska. Hagel, like Obama, is a member of the Foreign Relations Committee.

Obama, Reed, and Hagel were each allowed to bring one staffer on the trip to Afghanistan and Iraq. Blinken was the only additional staffer authorized to make the trip, giving Biden unique access to Obama's briefings and observations on the trip to both war zones.

Biden has taken on an increasingly visible role as a surrogate for Obama and went out his way this week to defend Obama's failure to hold a Foreign Relations subcommittee hearing on Afghanistan and the NATO-led effort there to battle the Taliban and its Al Qaeda allies. Obama had the power to convene such a hearing but did not as he was pursuing the nomination for the presidency.

When Biden ran for the presidency he called Obama's call in August 2007 for two more combat brigades in Afghanistan a "johnny-come-lately" position. Biden now defends Obama staunchly on all foreign policy matters and is viewed, if not as a running mate, then as a potential Secretary of State in an Obama administration.

This is Obama's first-ever trip to Afghanistan and Blinken, a former National Security staffer in the Clinton White House, could provide valuable expertise, in addition to keeping tabs on things for Biden.

Mike Emanuel currently serves as chief congressional correspondent for FOX News Channel (FNC). He joined FNC in 1997 as a Los Angeles-based correspondent.