HOMEWOOD, Ala. — Roy Moore defeated Sen. Luther Strange on Tuesday in a closely watched special election for an Alabama Senate seat, as frustrated Republican voters rebuked their party's leadership in Congress for failing to repeal Obamacare and deliver marquee promises.

Moore, the former chief justice of the Alabama Supreme Court, removed twice for ignoring federal court orders, won despite President Trump's endorsement of Strange. Angry Republicans in this low-turnout election sided with the candidate they perceived as the political outsider, versus the appointed incumbent who was defined by Washington and the support he received from Senate Majority Leader Mitch McConnell, R-Ky.

Moore led 56 percent to 44 percent with 74 percent of precincts reporting when the GOP runoff was called, winning all but a few counties in what amounted to an electoral wipeout. Strange, in a gracious concession speech, took full responsibility. He thanked Trump for taking a risk by endorsing him and urged Republicans to unify behind Moore in the December general election, although he stopped short of an official endorsement.

Strange said he'd never experienced a turbulent atmosphere in all his years in politics as he did throughout this stunning campaign.

"We're dealing with a political environment that I've never had any experience with," Strange told supporters gathered in a hotel near his home in suburban Birmingham, perhaps speaking for his shell-shocked Republican colleagues, who are wondering if the same is in store for them. "The political winds in this country, right now, are very hard to understand."

Moore, a fiery social warrior written off early in the race because of past defeats, emerged as the front-runner after round one of the special GOP primary, and never looked back. It was a sweet moment for his committed following. He pledged to take their mission to a Washington.

"I'll fight for you at U.S. Senate. I'll fight for the people of this state and this nation who want to bring our country back to its greatness. We can and we will," Moore told jubilant supporters gathered in an activity hall in Montgomery, the state capital.

The votes were tallied just as McConnell pulled the plug, yet again, on Senate legislation to repeal and replace the Affordable Care Act, President Barack Obama's signature healthcare law, because it lacked Republican support. Voters here, not to mention GOP insiders involved in the race, said Strange suffered for it — even though he was aligned with Trump and for the package, while Moore pledged to oppose it.

"I am sick — up to here — with these do-nothing Republicans," said Moore supporter Johnny Creel, 56, who lives and runs a small insurance agency in upscale, suburban Birmingham, the heart of Strange's electoral base and just down the road from where he resides. "I love the judge because he doesn't back down. Luther has jumped in bed with Mitch McConnell."

Moore is favored to win the special general election in December against Democrat Doug Jones. He led in most public opinion polls heading into Election Day, but his victory is still somewhat of an upset. His only previous statewide victories were for chief justice of the state supreme court, an elected position in Alabama; in 2012, he ran behind Republican presidential nominee Mitt Romney in the state.

Strange ticked up and narrowed the race, perhaps on the strength of Trump's endorsement, but his numbers in private campaign tracking had dropped back down to an insurmountable gap by Election Eve, the same evening that Vice President Mike Pence was rallying for him in Birmingham. Trump wished Moore well and reiterated his support for the new nominee in the next race.

"Congratulations to Roy Moore on his Republican Primary win in Alabama. Luther Strange started way back & ran a good race. Roy, WIN in Dec!" the president said in a Twitter post.

Some Alabamans said the incumbent couldn't lose the stench of corruption that voters here suspected after then-Gov. Robert Bentley, who was being investigated by Strange and eventually was forced to resign, appointed the then-state attorney general to succeed Sessions. Others said Republican voters were offended by the millions in negative ads that poured in from Washington-based groups linked to McConnell, namely the $9 million from Senate Leadership Fund, the majority leader's affiliated super PAC.

Republican operatives closely involved in this race and privy to internal data said those issues might have played a supporting role, but that disgust with Washington dominated. They warned that more upheaval in primaries was on tap if Republicans in Congress don't start getting big things done. That prospect appeared to chase Sen. Bob Corker, R-Tenn., into retirement. The pragmatic conservative called it quits Tuesday, announcing he would not seek a third term.

He might not be the last one.

Republican strategists involved in the Alabama race said Moore's victory boiled down to perceptions that Congress under Republican leadership was not delivering, symbolized by the GOP's failure to deliver an Obamacare repeal bill after seven years of promising to replace the Affordable Care Act, and voters' conclusion that Strange, as the incumbent, was a part of the problem, even though he supported Trump more than 90 percent of the time.

The day in early August when the Senate GOP bill to repeal Obamacare failed by one vote was "the worst day" of the campaign, and inflection point that Strange never recovered from, said a GOP operative who actively supported the senator. Strange's fate might have been sealed by the failure of Graham Cassidy, the second repeal pushed by Senate Republicans that was sponsored by Sens. Lindsey Graham of South Carolina and Bill Cassidy of Louisiana that symbolically was yanked from consideration the same day as the runoff.

It didn't help that Republican voters are absolving Trump of any responsibility for the dysfunction on Capitol Hill (possibly because he spent all summer channeling their anger via Twitter posts attacking the GOP Congress). So, even though his endorsement couldn't win a race in a state where his base is the strongest, which should be a blow to his influence, the president is unlikely to emerge from the special election with his star diminished.

"Roy Moore is more in alignment with what voters are looking for right now," a Republican strategist said, on condition of anonymity in order to speak candidly. "Voters are really, really pissed off and they want somebody to do something about it. Luther Strange was aligned with the guy that couldn't get Obamacare repealed."

But the outcome was sure to send shivers across the Republican Party, as officials brace for a wave of 2018 primaries from a populist Right energized by Moore's victory.

Steve Bannon, Trump's former chief strategist now back running Breitbart News, was active for Moore has made no secret of his plans to use this race as the first battle in a proxy war to bring down McConnell and Republican incumbents in the House and Senate. Establishment-oriented Republicans are also fretting that the megaphone of Capitol Hill will amplify Moore's provocative social conservatism, clouding the political fortunes of candidates running in targeted races.

Even here, in a state where Republicans are overwhelmingly conservative, some of Strange's voters say they cannot bring themselves to support Moore in the general election, even it if means ceding the Senate seat formerly held by Attorney General Jeff Sessions to a Democrat.

"I can't understand how a judge can sit there, and be removed twice, when your primary job is to uphold the law," said Jack Burnette, a 61-year-old financial planner from Birmingham who declared himself very satisfied with Trump's leadership. "I won't vote for Moore — ever. I wouldn't vote for Roy Moore for dog catcher."

Philip Wegmann contributed to this report from Montgomery, Ala.