Progressive taxation is the Dems ace in the hole. When close to 50% of voters have “representation without taxation” then that makes for a large structural advantage. Anyway, we know now that the Repubs will spend just as much, given the chance.
Seems to me that "given the chance" is the pivot point of your observation.
No longer can we go dormant on the day after election day. That old saw about the price of liberty equating to eternal vigilance comes to mind.
Step one ought to be making sure that Sen Foghorn knows she got elected only by the efforts of whatever the name of your local group is. The pain of voting against the folks back home needs to be greater than the pleasure of voting with the treasonous swine on the other side of the aisle.