Yes. If they have a valid warrant to search the home they can enter the home by force after they have "knocked and announced" their presence and no one answers the door.
More information is needed here. You should consult a qualified attorney in your state. The laws in Colorado are still undeveloped and there is no standard police procedure throughout each county in effect yet. The various counties are testing the limits of what they can get away with, which is why a qualified attorney may greatly assist you in this matter.
Disclaimer: Provision of the foregoing response does not create an attorney-client relationship, does not constitute legal advice, and should not be relied upon because the response is based upon the limited facts provided and it is impossible to meaningfully evaluate any legal problem without a thorough review of the pertinent facts and law which applies to the matter.