When you exit the Pennsylvania Turnpike just north of Pennsylvania, on Main Street in working-class Norristown, you’re in the overwhelmingly Democratic 13th congressional district — at least for a couple of miles. The help-wanted signs are in Spanish; people walk past the Premier Barber Institute, bail bondsmen, and the 99-cent stores wearing branded short-sleeve shirts from their chain-store jobs.

But come around a corner and up and hill and suddenly the neighborhoods turn leafy and green. Suburban-looking dads walk large dogs with flowing tresses. The houses are lovely and set back from the road. This three-quarter-mile stretch is in one of the nation’s most infamously gerrymandered districts, Pennsylvania’s reliably Republican seventh, a one-time swing district so wildly drawn that it resembles Donald Duck kicking Goofy. Signs warn drivers not to tailgate.

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Meanwhile, Stanford professor Nate Persily, a nonpartisan constitutional law and voting rights expert who has drawn court-ordered maps in many states, suggested that the truly valuable information for redistricting does not come from a web browser.

“I don’t think this level of individual data makes any difference for the redistricting process,” he said. “The coin of the realm is political data at the census-block level. Most of this can be garnered from precinct-based election results, sensibly broken down according to various algorithms.”