Crossword puzzle clue "obama's community building grp"

Obama's community building grp.

Moderator of the first Obama/McCain and Obama/Romney debates

___ center (building for community activities)

School community grp.

Basic building block of basic building blocks

Building block of a building block

___ Building, company headquarters erected in 1908 in New York City, at the time the tallest building in the world

Bridge building grp.