Why it is rational to vote

I'd be interested to know what HN'ers think one should do if there is no obvious frontrunner.

For example, if there are candidates A,B and C but none of them represent voter X well enough.

Another question. Which has more effect? Voter X voting for candidate A,B or C OR voter X creating monetary value through process N and then using that to put forth a candidate (presumably in 4 to 12 years) that represents voter X well.