When does high median income push a community leftwards or rightwards?

[ProgressiveModerate]

I would say in most US cities, if you look at the precincts/census tracts with the super high median incomes (like >250k/year), said precincts tend to vote more R than the surrounding communities, even if said communities are otherwise demographically simillar.

Good examples would be University Park in Dallas, Creek Village in Houston, McLean in Virginia, Buckhead GA, the Upper East Side of Manhattan and much of the Southeast Florida waterfront.

However, in other cases, it seems high median income communities are more liberal than their neighbors.

Good examples include many of Boston's western suburbs, wealthy parts of Bucks County, PA, Westchester NY, ect

When is wealth a proxy for a community voting more D, and when is it a proxy for voting more R?

[kwabbit]

In places like NOVA, Manhattan there is a good natural experiment for the effect of income on voting. Income and education are highly correlated but education is the much more important factor. In the aforementioned places, the surrounding area is also >80% college educated, allowing the income effect to be teased out.

In a place like Bucks County, however, the richest areas also are the most educated by a substantial margin. Education effect exceeds income effect, thus they are bluer.

[King of Kensington]

In Westchester County, you'll find a lot of "liberal elite" communities that are very D like Pound Ridge, and Scarsdale.  Meanwhile the more middling white communities and especially the heavily Italian areas are more R.

[Bismarck]

When education and religion are held constant you see an increase in republican voting as you move up the income spectrum.