Former Vice President Joseph R. Biden Jr. has maintained a steady but slightly narrowing lead in Arizona vote tallies after Election Day, with Latino voters lining up behind the former vice president in a state that President Trump won by three and a half percentage points in 2016.
As of early Thursday, Mr. Biden led Mr. Trump in Arizona by 68,400 votes, or less than three percentage points. In the votes so far from Maricopa County, which includes Phoenix, Mr. Biden leads by five percentage points, with about 5 percent of the total vote still outstanding.
Even Mr. Biden’s narrow edge underscored a profound political shift in Arizona, a longtime Republican bastion that has lurched left in recent years, fueled by rapidly evolving demographics and a growing contingent of young Latino voters who favor liberal policies.
The count was delayed in the early hours of Thursday, as dozens of Trump supporters demonstrated outside the Maricopa County election office where the votes were being counted.
In one of the brightest spots for Democrats so far, the former astronaut Mark Kelly defeated the state’s Republican senator, Martha McSally, in a special election, making Mr. Kelly and Kyrsten Sinema the first pair of Democrats to represent Arizona in the Senate since the 1950s.