Nebraska ? Republican Sen. Chuck Hagel plans to accompany Democratic presidential candidate Barack Obama on an upcoming trip to the Middle East, fueling speculation about the Nebraska politician’s future.

Both senators have confirmed the summer trip to U.S. battlefronts in Iraq and Afghanistan, which will also include Democratic Sen. Jack Reed of Rhode Island.

Hagel served as an Army sergeant in Vietnam and was twice wounded in 1968, earning two Purple Hearts. Reed, a West Point graduate, was a former Army Ranger and paratrooper.

Each has been mentioned as a potential running mate for Obama.

Hagel, a sharp GOP critic of the war in Iraq, has not endorsed Obama or Republican John McCain. His vocal criticism of the Bush administration has resulted in speculation that if Obama were to pick a Republican to serve as his vice president or in his Cabinet, it might be Hagel, who isn’t seeking a third term.