The final attempt in the Trump coup will come on January 6 (7 in NZ) when Trump acolytes will try and overturn the result of the Electoral College electing Biden.
It is worth noting there are two sources of law for what happens at the counting of the vote – the Constitution and the Electoral Count Act.
The provisions of the Electoral Count Act are subservient to the constitution. Nothing in that Act can be used to undermine the actual constitution. So if (for example) Mike Pence (as Trump wants him to) declared Trump elected, a court would rapidly reverse it.
So what does the constitution say:
The Electors shall meet in their respective states and vote by ballot for President and Vice-President, one of whom, at least, shall not be an inhabitant of the same state with themselves; they shall name in their ballots the person voted for as President, and in distinct ballots the person voted for as Vice-President, and they shall make distinct lists of all persons voted for as President, and of all persons voted for as Vice-President, and of the number of votes for each, which lists they shall sign and certify, and transmit sealed to the seat of the government of the United States, directed to the President of the Senate; — The President of the Senate shall, in the presence of the Senate and House of Representatives, open all the certificates and the votes shall then be counted
So the constitution says the job is to count the votes. That’s it.
Now the Electoral Count Act 1881 has further provisions, but again remember these provisions do not override the constitution. They say:
Upon such reading of any such certificate or paper, the President of the Senate shall call for objections, if any. Every objection shall be made in writing, and shall state clearly and concisely, and without argument, the ground thereof, and shall be signed by at least one Senator and one Member of the House of Representatives before the same shall be received. When all objections so made to any vote or paper from a State shall have been received and read, the Senate shall thereupon withdraw, and such objections shall be submitted to the Senate for its decision; and the Speaker of the House of Representatives shall, in like manner, submit such objections to the House of Representatives for its decision; and no electoral vote or votes from any State which shall have been regularly given by electors whose appointment has been lawfully certified to according to section 6 of this title from which but one return has been received shall be rejected, but the two Houses concurrently may reject the vote or votes when they agree that such vote or votes have not been so regularly given by electors whose appointment has been so certified.
Under the ECA, a state’s electoral votes can be rejected if both the House and Senate decide they are improper. This won’t happen as the Democrats have a majority in the House. But even if say the GOP had a majority in the House and Senate and they voted to reject a state’s votes to try and steal the election, there is no way it would survive court action. Because nothing in the ECA can over-ride the constitution and the constitution does not give Congress the power to decide who won the election. Their constitutional job is only to count the vote.
What will be of real interest on the 6th is how the Repuplicans representatives and senators vote. Will they vote to appease Trump (as not doing so may generate a primary challenge) or will they vote to uphold democracy?
If they vote for Trump they are less likely to have a primary challenge but more likely to lose in the general election (unless in a very safe seat).