Attendance
The Constitution specifies that a majority of members constitutes a
quorum to do business in each house. Representatives and senators
rarely force the presence of a quorum by demanding quorum calls; thus,
in most cases, debates continue even if a majority is not present. The
Senate uses roll-call votes; a clerk calls out the names of all the
senators, each senator stating "aye" or "no" when his or her name is
announced. The House reserves roll-call votes for the most formal
matters, as a roll-call of all 435 representatives takes quite some
time; normally, members vote by electronic device. In the case of a
tie, the motion in question fails. In the Senate, the Vice President
may (if present) cast the tiebreaking vote.