on the fence

(idiom) to be unable to make a difficult decision about two or more possibilities

Example Sentences:

A: Are you going to vote for John McCain or Barack Obama?
B: I’m not sure, I’m still on the fence. What do you think?
A: I think you are an idiot.

The confused high-school graduate was on the fence about whether to be a doctor or a lawyer.

Media:

Similar idioms:

1. zoned
2. fork in the road
3. ace a test
4. IMO
5. leave someone high and dry