“They’re going to attach Obama to us as much as humanly possible,” said a Democratic strategist involved in the race. “That argument will be made regardless of what we do.”

Pryor, who has described himself as “nonpartisan,” took pains last year to distance himself from the president during the campaign, at one point saying it was “totally secondary to me” whether Romney or Obama won.

“I’m not there to represent a president,” the two-term senator said.

The failure to be vocally supportive of the first African-American president and his agenda on everything from immigration to guns already appears to be dampening enthusiasm among some African-Americans. Fourteen percent of registered Arkansas voters are black.

“There are many African-Americans who are quite bothered by some of the votes that Sen. Pryor has taken,” said Joyce Elliott, vice chairwoman of the Arkansas Democratic Party and the former state Senate majority leader. “I’ve had lots of conversations with African-Americans who just don’t want to even talk about it, who say, ‘Maybe I just won’t vote.’”