Can large brackets be referred to cells in a SUMPRODUCT formula?

Hi, everyone, large brackets can be applied in a SUMPRODUCT formula like:

=SUMPRODUCT(--((A1:A100={"United Kingdom","Germany"}),B1:B100)

But the formula below will fail:

=SUMPRODUCT(--((A1:A100={C1,C2}),B1:B100)

I can certainly expand the formula to:

=SUMPRODUCT(--(A1:A100=C1),--(A1:A100=C2),B1:B100)

But if I have too many keywords C1, C2, ... C100, then it is a burn to write a long formula like the above.

Is there a way to write a concise formula accommodate all these C1, C2, ... C100?

Thank you, tim201110. It works perfectly. Thank you so much.