WASHINGTON — Republican Rep.-elect Dan Bishop's narrow victory in a North Carolina special election had drawn a half-dozen excited tweets from President Donald Trump by early Wednesday morning.

"Dan Bishop was down 17 points 3 weeks ago. He then asked me for help, we changed his strategy together, and he ran a great race," Trump tweeted. "Big Rally last night."

A 2-point win in a district that Trump carried by 12 points in 2016 qualified as "monumental," he said in a phone call with Bishop — and on one level it's hard to argue with that interpretation in the context of Trump's sub-40 percent national approval rating, the drubbing his party took in the 2018 midterm elections and an ever-more-chaotic administration atmosphere that saw the firing of his third national security adviser in less than three years on Tuesday.

North Carolina special election: Full results and map

But as a matter of measuring his standing before he faces voters next year, barely holding onto turf that's been in Republican hands for decades — where he himself jetted in for a last-minute rally to pump energy into the GOP base Monday night — should be cause for the president to sound alarm bells in his ranks rather than blast triumphant notes from his own horn.

"Republicans should feel relieved they avoided a loss, but here's why Bishop's 2% win isn't encouraging: There are 35 GOP-held House seats less Republican" than North Carolina's 9th District, David Wasserman, House editor of the nonpartisan Cook Political Report and an NBC contributor, wrote Tuesday night.

While Trump's charge is different than that of House Republicans — he has to win state-by-state to take an electoral college majority, while they play district-by-district to try to recapture control of the House — the political dynamics are related. The results Tuesday night demonstrated that, at least outside Charlotte, Republicans aren't winning back many in the vote-rich suburbs they lost in the 2018 midterms.

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And yet Trump could take satisfaction in one obvious subplot. The district includes a portion of Fayetteville's Cumberland County, and those precincts had favored the Democrat in the last House election. They were Trump's target when he held the rally for Bishop on Monday at the Crown Expo Center in Fayetteville, tucked just inside the 9th District.

On Tuesday, Bishop won the Cumberland County part of the district by six votes.

No two races are exactly alike, but this one was a reasonably good bellwether because it was a do-over of a tainted contest from November in which Republican Mark Harris defeated Democrat Dan McCready by four-tenths of a point amid allegations of election fraud. This time, fewer than 190,000 people voted, compared to almost 283,000 in November.

The key takeaways: Bishop out-performed Harris in rural areas, and McCready beat his own numbers in suburban Mecklenburg County — increasing his share of the vote there from 54.9 percent to 56.3 percent.

Trump strategy for winning re-election relies heavily on massive rural Republican turnout in swing states — as it did in 2016 — but some Republicans have privately questioned whether he can win if he doesn't find a way to reclaim some of the suburban voters he's alienated during his presidency.

Frank Luntz, a veteran pollster and message-maker for GOP candidates, likened Bishop's win to a heavily favored college football team hanging on in the final minutes against an opponent that shouldn't have been in the ballgame.

"Conservative Twitter celebrating a 2-point win in a +12 GOP district from 2016 is like Michigan celebrating a win over Army in double-overtime," he wrote on Twitter.

Of course, Tuesday night's election was just one of 435 House races, run in the vacuum of a special election in an off-year between midterms and the next presidential contest. But it serves as another data point — along with many months of polling on the president's approval rating, voters' attitudes and head-to-head matchups between Trump and potential Democratic foes — that suggests he has a lot of work to do to reclaim voters and political turf he's lost since 2016.

Nothing Trump has done so far — including taking a self-congratulatory victory lap Tuesday night and Wednesday morning — suggests he's heard that wake-up call yet.