Could the Electron in combination with it's kickstage deliver any meaningful mass to Mars, ie; a 2kg cubesat or is it unable to reach the required velocities even with no payload. Rocketlab are offering a service of around 20kg to a Lunar orbit and recently got the award for the CAPSTONE mission, and getting to a Lunar orbit from memory isn't that much more extreme compared to just getting a Mars flyby.
Recently in an interview with Micheal Sheetz, Peter Beck mentioned that the Electron
“We actually showed that we could not only get to the moon, but we can do near-interplanetary stuff. We can go to Venus, we can go to Mars,” Beck said.
Then in an interview with Everyday Astronaut, he said;
"we can even get 20 odd kilograms to Venus"
Note: The Photon kick stage isn't a set design and for this interplanetary mission it would be upgraded, to become beefier. This would be done by adding more fuel tanks.
Since Mars is more delta-V intensive than Venus, it's fair to assume that the payload is less than 20kg, but still greater than 0kg. So yes, Electron with an upgraded Photon could launch a cubesat to Mars.