Constitutional? The process is set forth in the constitution. We can argue about what it means, and a feckelss VP like Pence can argue it means nothing and that the VP is just there as a figurehead and maybe that's the case, maybe it isn't. But if the dems don't like the words in the constitution, then they can change them if they can get 2/3 of the house and senate to go along, along with 3/4ths of the states.
See Post #18. The issue isn’t the Constitution. It’s the Electoral Count Act of 1887 that is a major problem.