Estes received 53 percent of the vote in Kansas's 4th Congressional District, compared to Thompson's 46 percent. Former Republican congressman Mike Pompeo won the seat by 31 percentage points in November.
Especially in a special election, most voters aren't paying much attention to the candidates when they go to vote, said Stuart Rothenberg, a nonpartisan elections analyst and columnist at The Washington Post.
The contest had been a sleepy affair until last week when the campaign arm of House Republicans spent $100,000 on ads attacking Thompson at the last minute.
Yet even before the results were in, Democrats claimed victory in defeat, noting how much Estes was underperforming typical Republicans in the district, how energized Democratic voters are, and that several upcoming special elections, not to mention the 2018 midterms, will happen on more friendly turf.
The Estes campaign pulled in Senator Ted Cruz of Texas to campaign Monday Wichita.
Trump recorded a robocall for Estes in the campaign's final days and took to Twitter on Tuesday morning to promote him. Nor was Rep. -elect Ron Estes, the state treasurer, a particularly flawed GOP candidate. It's true that late polling had Estes underperforming, having dropped into a virtual tie with Thompson with just a +1 edge. Democrat Xavier Becerra left the House in 2016 and successfully ran for California State Attorney General, leaving the 34th district open.
Thompson already is looking ahead to next year's election, when the 4th District seat will be up for grabs. Estes also worked in the aerospace, oil and gas, and manufacturing industries.
"A wonderful guy", Trump tweeted about Estes on Tuesday. "And we knew they would show up, and they did show up". His campaign, inspired by Sen. Bernie Sanders' presidential campaign previous year and chose to run for Congress.
The Democratic Congressional Campaign Committee, the NRCC's counterpart, closely monitored the race and eventually did 25,000 live phone calls to get out the Democratic vote there. "For sure, I will have rural support", she said she thought.
In the end, the race to fill now-CIA Director Mike Pompeo's seat in Congress wasn't as close as some thought, but closer than it normally would have been. "We'll come back in 2018 stronger and be able to win it".
Another race in the suburbs of Atlanta, to replace Republican Tom Price, who's now secretary of Health and Human Services, has become extremely competitive. In addition, there is a huge field of mostly Republican candidates who have trained their fire on one another, while documentary filmmaker Jon Ossoff largely has had the Democratic field to himself.
Congressional elections are zero-sum affairs: candidates vie for a seat, the victor earns the opportunity to serve, and the loser gets nothing.