Your vertexdata are almost equal. I mean your line is very small. Replace your code with the following and use a valid Projectionmatrix:
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glScalef(1,1,1);
gluLookAt(1.8,1.8,1.8, 0,0.6,0, 0,1,0);
glBegin(GL_LINES);
glVertex3f(0.32780680060387, .66463083028793, 0.20269837975502);
glVertex3f(1.32780680060387, 0.66547948122025, 0.20269837975502);
glEnd();
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and use the Up-vector (0,1,0) (the last 3 gluLookAt(…) values) for the direction of the viewing volume.