That's essentially how a jet engine works but replacing the combustion chambers with electric heaters - and it sounds really expensive in terms of power consumption. An alternative is a kind of plasma propulsion engine called a VASIMR [0] engine.

I don't want to do the napkin math but my gut is the most practical electrical mechanism to get enough delta-V to LEO is a railgun but doing the acceleration up front would have probably have undesirable effects on the payload.

[0] https://en.wikipedia.org/wiki/Variable_Specific_Impulse_Magn...