I think that the reader can identify with the narrator in "Cathedral," making him a sympathetic character.

The narrator is a sympathetic character from the story's opening.  The narrator talks about how his "idea of blindness came from the movies."  This detail makes us relate to the narrator because of it shows how biased we can be.  We see the narrator as sympathetic because many of us have been in similar situations where something external has formed our initial predispositions.  The narrator is also sympathetic because he initially does not want his world to be disrupted.  We can relate to someone who says that a visit "was not something I looked forward to."  In these ways, the story opens with the narrator as someone towards whom we have sympathy or with whom we can identify.

The ending of the story is another instant where we experience sympathy towards the narrator.  He has shared a moment with the blind man in the drawing of the cathedral.  When the blind man tells the narrator to keep his eyes closed, he must try something new.  He experiences life from another person's point of view.  This experience makes us feel sympathy towards him. We identify with him because we see how much a casual encounter has changed him.  It creates sympathy because we understand how important it is to be open to new experiences in our lives.  

In "Cathedral," do you think that the narrator is portrayed as a sympathetic character?

Many people like Raymond Carver, but some do not like him at all. His viewpoint character in "Cathedral" is pretty much the same as his viewpoint character in many other stories, including "Where I'm Calling From," "Boxes," and "Feathers," as well as his speaker in many poems. The narrator is indistinguishable from Carver himself. One of the things that people who like Carver like about him is his complete honesty. He had many faults, and he not only confesses to them, but he used them to create his fiction and poetry.

Carver was a heavy drinker and a heavy smoker. He used drugs. He was so improvident that he twice filed for bankruptcy. He died of lung cancer at an early age from smoking. Characteristically, he writes about his feelings about lung cancer in a poem titled "What the Doctor Said." In "Cathedral" it is obvious that the narrator is not getting along with his wife and that they may be headed for divorce.

The narrator of "Cathedral" is obviously a shy, socially awkward, anti-social introvert who likes to drink, smoke tobacco and pot, and watch television. He doesn't like his job. Carver had many jobs and didn't like any of them. The only work he liked was writing stories and poetry, and he didn't make enough money from these pursuits to live on until the end of his career. Since he and his wife married young and had two children, it is easy to see why she would have been chronically dissatisfied with him.

The narrator is Carver thinly disguised. People who find this narrator sympathetic are the same people who also like Carver. They like him in spite of his faults. Two of the traits they like best about him are his total honesty and his wry sense of humor. Although many stories and poems are terribly sad, there is almost always that characteristic quirky sense of humor to be seen in them. Typical examples of Carver's humor to be found in "Cathedral" are the following.

"Maybe I could take him bowling," I said to my wife.

The narrator knows this is going to antagonize her, but he can't help saying it. Maybe Carver's essential problem was that he couldn't control his impulses. He knew when he was doing or saying the wrong thing but went ahead and did it anyway. The image of a blinid man bowling popped into his head and popped out of his mouth.

"Did you have a good train ride?" I said. "Which side of the train did you sit on, by the way?"

"What a question, which side!" my wife said. "What's it matter which side?" she said.

The narrator is not just commiting a faux pas. He is a little hostile toward this blind stranger because he feels jealous. Robert and the narrator's wife have been corresponding by recording tapes for ten years. No doubt she has told Robert a lot about her husband, and he knows that she could hardly talk about him without revealing some of his many faults. So he is defensive as well as jealous. But many readers can identify with the narrator. We feel funny about blind people. We feel jealous of a spouse's former close friends. We often feel de trop, as the French say, when we are the third member of a trio in which only two have anything in common or anything important to talk about.

If you like Raymond Carver, you will find his narrators and viewpoint characters sympathetic, including the shy, awkward, self-conscious narrator of "Cathedral." If you don't, you won't. Many critics hated Carver when he was struggling for recognition. Then when he became successful as a writer, they hopped on the bandwagon.