Earlier quoted context omitted.
Then it's time to fight back. Make it absolutely clear to McConnell and Democratic leaders in the Senate that if McConnell fills this seat in an election year, then the Democrats must increase the size of the SCOTUS. McConnell needs to fear the reprisal more than he fears the delay. Because you're right, this is about power. Nothing else matters to them. So make them fear this.
You can expand the number of seats on the Supreme Court via a bill passed by both houses of Congress and signed by the president. So we'd need the presidency, a majority in the House, and a supermajority in the Senate to invoke cloture to end the inevitable legislative filibuster from the Republicans. So even with a blue wave in November, that's not possible because it is extraordinarily unlikely that we gain a super…
This is what I call for in another comment. There's no way to get a supermajority in the Senate, so the legislative filibuster would have to die.