Ravens owner Stephen Bisciotti said Sunday such a move would "upset some people," per Martin.
"I hope we do what is best for the team and balance that with what is best for our fans," Bisciotti said, via Martin. "Your opinions matter to us. We're very sensitive to it, and we're monitoring it, and we're still, as [general manager] Ozzie [Newsome] says, scrimmaging it, and we're trying to figure out what's the right tact. So pray for us."
The Baltimore Sun's Jeff Zrebiec noted Cass said the team is weighing the decision. Bisciotti also said he had spoken with former Raven Ray Lewis and current players about signing Kaepernick.
NFL Network's Ian Rapoport called the Kaepernick-Ravens conversations "very real" and tweeted that it "sounds like this is becoming more of a possibility."
Kaepernick has been outspoken about social issues and protested last season what he said is "a country that oppresses black people and people of color" by taking a knee during the national anthem before games. New York Giants owner John Mara told The MMQB's Jenny Vrentas in May the Giants had received significant feedback from fans who voiced their displeasure over the possibility that a Giants player could protest like Kaepernick.
The Ravens have an opening at quarterback—at least for the time being; Rapoport and NFL Network colleague Tom Pelissero reported Wednesday that Joe Flacco could miss up to six weeks with a back injury.
On Thursday, Baltimore head coach John Harbaugh said he had built a relationship with Kaepernick, which began when John's brother, Jim, coached the 49ers during Kaepernick's first four years with the team. Harbaugh also said the Ravens had at least considered bringing Kaepernick aboard.
"He's a guy right now that's being talked about," he said, per USA Today's Michael Middlehurst-Schwartz. "We'll see what happens with that. Only speculation right now. He's a really good football player, and like I said, I do believe he'll be playing in the National Football League this year."
Kaepernick would be strong competition for Baltimore's current backup, Ryan Mallett. In 19 career NFL games, Mallett has thrown for 1,779 yards and seven touchdowns with 10 interceptions.