In a column titled The Clinton Agenda, New York Times columnist Paul Krugman lays out the case for why Hillary needs to not just win, but win big and what happens if does.
First, the most obvious part: A landslide win gives us the Senate. That, in turn, gives us the Supreme Court. Why does that matter? Simple.
...bear in mind that climate change is by far the most important issue facing America and the world, even if the people selecting questions for the presidential debates for some reason refuse to bring it up. Quite simply, if Democrats take the Senate, we might take the minimum action needed to avoid catastrophe; if they don’t, we won’t.
There is a stunning amount of environmental work that can be accomplished by the president and Republicans, once loathe to rely on the courts, have used the Supreme Court to block as much as possible. Take the Court away and things get better no matter how loudly Republicans howl.
But if action on Climate Change is too abstract for you, here's a more immediate and concrete reason Hillary must win in a landslide, even if you hate her guts: Democrats can temporarily take back the House.
Even with gerrymandering and voter suppression laws, if Hillary beats Trump by double digits (something not seen since 1984), there's a real possibility that such a landslide would overcome the baked-in advantage Republicans created for themselves. We would lose the House 2 years later if the gerrymandering remains but a lot can happen in two years and Hillary has been very clear what she would do with that time:
Broadly speaking, she would significantly strengthen the social safety net, especially for the very poor and children, with an emphasis on family-related issues like parental leave. Such programs would cost money, although not as much as critics claim; she proposes, credibly, to raise that money with higher taxes on top incomes, so that the overall effect would be to reduce inequality.
Democratic control of the House would also open the door for large-scale infrastructure investment.
Such a redistribution of wealth would be of immeasurable benefit to the country. The rich will still be rich but they won't be that way at the expense of the rest of us (as much). But even more important would be the very unsexy but oh-my-god-we-need-it infrastructure spending.
Quick history lesson: One of the things Republicans did when they took control of the House in 2010 was to immediately slash infrastructure spending:
Infrastructure spending is fantastic for the economy because it cannot be outsourced and every penny gets pumped into the local economies where the construction is taking place. It creates a lot of good paying jobs and has the knockdown effect of giving us safe and roads, bridges and dams which have their own economic advantages. So of course Republicans choked it off for the sole purpose of denying Obama an easy way to goose the economy.
When Republicans were screeching "Where are the jobs?" The answer was always "Being blocked for obnoxiously partisan reasons by people who hate the Middle Class."
Right now, the economy is just tipping over from steady but somewhat sluggish to strong and vital. Wages are finally rising and people are not hurting as badly. If Clinton gets a Congress that's not dedicated to obstructing her every move, the infrastructure spending alone would increase the average wage by a significant amount, accelerating the virtuous cycle of consumption, wage growth and job creation.
It's not as catchy as "Single Payer" or "Tuition-Free College" but if we crush Trump at the polls and give Hillary a Congress that will actually work with her, we can finally take real strides towards combating Climate Change and having an economy that really does work for all of us instead of just the wealthiest 1%.