how to use gnu parallel and grep with a space

[Shantanu Unknown]

Hello,

I am trying to use gnu parallel and grep as follows

cat tmp | parallel -j1 grep  "^{} " ~/datafile.txt 

(notice one space between {} and ")

One line in tmp contains 101

and unfortunately with the above statement I get

101 299.2599 -3.6514901

1013 185.00003 -6.7468192

1014 188.6323 9.7729794

which I don't want

grep "^101 " datafile.txt works fine though

I changed grep  "^{} "

with grep  "^{}\"

but that too gives same results as before.

Is there an easy solution for this?

Thanks

shantanu