In order to run for federal office in the US, you will be required to use government-approved software (see §306). If none is available for your chosen platform -- assuming you use computers at all
Sure, we can hope that such software will be available for other platforms, and there is nothing in the legislation that prohibits someone from developing such software, but still
FWIW, the software in question is for recording/reporting of camapaign finance information.
The only loophole I see is "once such software is made available to such candidate." One might argue that if I use Mac OS or Linux, and you give me Windows software, then you have not indeed made available to me any "such software," where such software is software that "permits this, allows that, allows another thing" since it does not permit or allow anything for you, not being a Windows user.