DC-X.
From Wikipedia:
# dry mass: 9100 kg
# GLOW: 18,900 kg
From here, the RL-10's exhaust velocity is: 4.53 km/s.
Delta-V (assuming no losses) to LEO is 9.8 km/s. The rocket equation says: delta-v = ve * ln(m0/mi). Assuming no payload it had a delta-V of approximately: 3.31 km/s. Not even a third of the way to orbit.
Like I said...then physics got in the way.