DUNWOODY, Ga. — Republican Karen Handel has won a nationally watched congressional election in Georgia, avoiding an upset that would have rocked Washington ahead of the 2018 midterm elections.Incomplete returns show Handel winning almost 53 percent of the vote over Democrat Jon Ossoff, who won about just over 47 percent in Georgia's 6th Congressional District. That margin allows Republicans a sigh of relief after what's being recognized as the most expensive House race in U.S history, with a price tag that may exceed $50 million.Yet the result in a historically conservative district still offers Republicans a warning that President Donald Trump's tenuous standing will dominate the looming campaign cycle. Georgia's outcome follows similar results in Montana, Kansas and South Carolina, where Republicans won special House races by much narrower margins than they managed as recently as November.Republicans immediately crowed over winning a seat that Democrats spent $30 million trying to flip.