Bristling at hecklers and weathering a generally cold audience, Rep. Jim Moran on Saturday told hundreds of Tysons tunnel supporters he won’t “be a cheerleader” for the underground track.

Moran, D-8th, delivered a downbeat assessment for the tunnel concept, which supporters hope to revive as part of the 23-mile Dulles Corridor Metrorail Project. Gov. Tim Kaine abandoned the popular idea in September after the Federal Transit Administration warned it would put $900 million in federal funds in jeopardy. Supporters, however, have since massed a groundswell of local pressure to bring the tunnel back.