sentences:  Dennison had owned and operated gambling houses such as the Opera House Gambling Saloon in Leadville, Colorado and the Board of Trade saloon in Butte, Montana.Tom Dennison was thirty-four when he arrived in Omaha with $75,000 in cash.Upon surveying the city, he found Omaha to be a "wide open town", meaning there was little legal control over gambling, liquor, prostitution and other criminal interests.