Democrat Conor Lamb declares victory in Pennsylvania race

CANONSBURG, Pa. — Democrat Conor Lamb declared victory early Wednesday morning in his bid for a Pittsburgh-area House special election, although the race hasn't yet been called.
The district, which voted for President TrumpDonald John TrumpScarborough mocks 'Deflection Don' over transgender troop ban Pelosi condemns Trump's 'cowardly, disgusting' ban on transgender troops Trump moves to ban most transgender people from serving in military MORE in 2016 by a 20-point margin, was once considered an easy win for Republicans. But Lamb currently leads Republican state Rep. Rick Saccone by 641 ballots, with 100 percent of the precincts reporting, according to The Associated Press
"It took a little longer than we thought, but we did it. You did it," Lamb told supporters at his election night party shortly before 1 a.m., after he was introduced as "congressman-elect." 
"We followed what I learned in the Marines — leave no one behind. We went everywhere, we talked to everyone, we invited everyone in." 
Lamb's campaign apparently believes that Saccone does not have a path to victory in the remaining ballots, leading to the decision to claim victory.
Saccone promised earlier in the night to press on, with his campaign telling MSNBC shortly after Lamb's remarks that they will not concede at this point. Media outlets have also not yet called the race. 
The razor-thin margin is yet another shocking moment in this special election, which had initially been seen as a GOP cakewalk but that has trended in the Democratic direction in recent weeks. 
Republicans sunk more than $10 million into the 18th District to boost Saccone, sending top surrogates like Trump to the area. But Lamb walked a fine line in the conservative district, bucking the national party on some key issues and rallying labor to his side. 
Lamb devoted a significant portion of his victory speech to thanking union members, a group that had been seen as key to Lamb's campaign. 
"Side by side with us at each step of the way were the men and women in organized labor," he said. 
"Organized labor built Western Pennsylvania. ... Tonight, they have reasserted their right to have a major part in our future."
And while he did not mention Trump's name, he made it clear he would seek cooperation with the president, who remains more popular in this district than in national averages. 
"I'll work on the problems our people face, secure their jobs and pensions, protect their families. And I will work with anyone to do that," he said.  
Updated at 6:22 a.m.