The quotation:
As expected, the Cornell-Harvard game was tense, hard-fought and punctuated with dramatic momentum swings. With ten minutes left to play, the score had been tied ten times and the lead had changed eight times.
This seems to be
from Outside the Limelight: Basketball in the Ivy League, by Kathy Orton.
Solutions to clues:
A. OMEN (substring)
B. RAWHIDE (WH in RAID + (-whos)E)
C. TAP DANCE (reverse cryptic)
D. OVERSLEEP (O + VERSE + EP, containing L)
E. NATTY (apparently this means "national college football championship" or something, and UGA really have wone it two years in a row)
F. OMBUDSMAN (M(-y) + BUDS in OMAN)
G. UFF DA ((-d)UFF(+d) + A; one must imagine this as a Down clue)
H. THWART ((RAW + H(-am))< in two Ts)
I. STRENGTH (ST + (L->R)ENGTH)
J. IMPEND (IMP + END)
K. DILETTANTE (TALENT* in DIE, around T)
L. ECCENTRIC (ECCE + TRIC(-king), installing N)
M. THEME (regularly spaced letters)
N. HATCHED (HATCHE(-t) + D; I think "hatchet" is being used as a verb here so that "axe" can mean to remove its last letter)
O. ESTIMATE (MEATIEST*)
P. LAUGH (LUG around A, plus H; "kid" meaning "joke")
Q. ITEM (initial letters)
R. MADDEN (I think this is the name of a video game so ddef)
S. EXCLUDED ((-s)ECLUDED containing X)
T. LEWDNESS (reversed substring)
U. IN THE AIR TONIGHT (anagram, &lit)
V. GASHES (G + ASHES)
W. HOGWASH (HOGWARTS losing RT, plus H)
X. TAUT (U in TAT)
Credit where due: Part of the wordplay for G was figured out not by me but (in comments below) by Stiv. Part of the wordplay for L was figured out not by me but (in comments below) by M Oehm.