"Will Rogers phenomenon" state redistricting challenge

[Verily]

move Montgomery County, MD to Washington DC

DC goes from 93/7 Obama to 80/20 Obama.

MD goes from 63/37 Obama to 61/39 Obama.

Same applies with Prince Georges County and Arlington/Alexandria to DC

You can go more extreme than that and also annex Fairfax County (and Falls Church and Fairfax Cities) to DC. And also Howard and Charles Counties, as once MontCo and PG County are in DC, they are also more Democratic than Maryland. And you can also annex Prince William and Loudoun Counties to DC as well (and the Manassas cities).

Edit: Actually, you could then put Baltimore County in DC as well and make both more Republican. Not Baltimore City, though, as by that point DC would be less Democratic than Baltimore City. Anne Arundel and Frederick Counties could go into DC after Baltimore County, though.

[Verily]

I'm pretty sure moving Coös County

I learned something new today.

That there's a US county with an umlaut in its name?

That it doesn't rhyme with lose.

I thought it rhymed with loose. Regardless, apparently not.