I just don’t think that’s true. The corruption is so obvious everyone sees it including Republican voters who then point to Democrats and say, ‘But so are Democrats.’ And really if the argument is ‘Well, yeah, but not THAT corrupt. Or, but not corrupt in the same way’ the left has already lost.
Trump winning twice and the historic unpopularity of Democrats right now just bears that out. If voters are going to be governed by corruption they prefer it to be by those who are open and honest about it and not by a party that claims it’s different and then always finds excuses not to be better.