[snip because I don't have enough posts to include links]
Writing's on the wall for the GOP in Gwinnett, and he knows it. Just how far will the Gwinnett GOP fall? Consider the following:
1) In November 2018, Dems had no county commission seats, no countywide positions, one Board of Education seat, and 10 of 25 seats on the county General Assembly delegation. With the exception of BOE district 2 - Republican Steve Knudson held on by ~100 votes - every partisan county race was won by a Democrat. Both county commission seats, one BOE seat, and the Solicitor General office were all flips, and none of them were close. 8 General Assembly seats (2 Senate, 6 House) flipped to the Dems, giving them control of the county delegation.
2) The remaining Republican-held county commission seats are all up in 2020. The county commission district map is practically a dummymander (someone else has probably run the numbers, but I think Abrams won or came within a couple points of winning all of them).
In district 3, Tommy Hunter is heading for defeat - he managed to piss off almost half his constituents in 2017 by calling Democrats "Demonrats" and calling John Lewis a "racist pig", his attempts at making up for the comments weren't well-received; only reason he wasn't recalled is because offensive public commentary is not grounds for recalling an official in Georgia. He already had a close-race in 2016 (he won 51-49) and Abrams carried his district by a comfortable margin.
District 1's Jace Brooks was unopposed in 2016, but his district doesn't include the reddest parts of Gwinnett - Buford and the Hamilton Mill HS cluster - but rather Suwanee and many heavy-Dem precincts along I-85 north of Jimmy Carter Blvd. He's not quite as doomed as Tommy Hunter is, but he's in danger of losing.
Finally, Charlotte Nash is the chairwoman and thus will be on the ballot countywide. Nash has been relatively inoffensive, but I don't recall Solicitor General Szabo being offensive either - she still lost 54-42 last fall. Very likely the Dems win her seat, and it probably won't be that close.
In short, it's probable the county commission will go from all-GOP to all-Dem within the span of two years. Damn.
3) The Board of Education map is on the cusp of being a dummymander. As previously mentioned, Knudson held on in district 2, but his district takes in the ultra-red Hamilton Mill cluster, parts of ultra-red Sugar Hill, and the swingy and Dem-leaning precincts along GA Highway 20 from Lawrenceville to the Mall of Georgia. He only won by ~100 votes.
BOE District 3 and the chair position are up next year. District 3's incumbent Republican Mary Kay Murphy was unopposed in 2016, but Abrams won a majority of precincts in Murphy's district. This race is very ripe for a Dem flip. As is the chairman position, but that goes without saying as a countywide position.
Knudson's win means that the GOP will, at the very least, keep one position on the Gwinnett BOE.
4) Sheriff Butch Conway, the tax commissioner, and several countywide partisan court positions are also up. I suspect 2020 will not be kind to their reelection prospects considering what happened to Szabo in 2018.
5) P.K. Martin is in serious danger of losing his state Senate seat (SD-9). Harrell is completely done for in HD-106 (he was unopposed because of a Dem fail in qualifying, but Abrams carried his seat by 15 points,) and HD-104 (Efstration's seat) will be close.
In short, Gwinnett is a complete dumpster fire for the GOP and they're losing their grip on all levels of power in the county. Danny Porter running for reelection as a Dem is the only way he can hold the office short of a Dem qualifying failure.