I'd go with something like this:
DECLARE
@Now datetime,
@Today datetime,
@Tomorrow datetime
SELECT
@Now = GetDate(),
@Today = DateAdd(dd, DateDiff(dd, 0, @Now), 0),
@Tomorrow = DateAdd(DAY, 1, @Today)
SELECT * FROM ABC WHERE TDate >= @Today AND TDate < @Tomorrow
Note that I borrowed some of that code from
ewbi.blogs.com. You'll note that I only calculate the date once (well, twice if you want to be picky). You will get better indexing performance if you apply calculations to the value you are comparing against rather than the column you are comparing against.