Mass vaccination clinics aimed at combating H1N1, or swine flu, have begun across Colorado. But the supply of vaccine here remains short, as it does nationwide. Far more people want the vaccine than can have it at this point. Health officials are struggling to get what vaccine they do have to people at highest risk, and asking the rest of the public to remain patient. KCFR Health Reporter Eric Whitney went to some of the first mass vaccination clinics in the Denver metro area and has this story.