1988 Other Subaru Models Having problems starting & runs

So I get in the car to start it (usually you would just engage the clutch to start) but for the past 2 months I've had to engage the CLUTCH and the GAS in order for it to start. After about 5 tries it starts and I have to keep my foot on the gas pedal in order for it to stay running for a couple of minutes. The outside temperature does not seem to affect this problem. My car does run ROUGH as well it seems like it's not getting the GAS properly, so this is why I thought it was the fuel pump, 1.5 months ago I'd replaced the fuel filter. Do you think it's the pump or could it be electrical? Thank you!