Allard was born in Fort Collins, Colorado and raised on a ranch near Walden, Colorado. He received his Doctorate of Veterinary Medicine from Colorado State University in 1968. While completing veterinary school, Allard married Joan Malcolm who received her degree in microbiology, also from CSU. They built their veterinary practice , the Allard Animal Hospital, from scratch. The Allards raised their two daughters, Christi and Cheryl, in Loveland, Colorado and have four grandsons.
Allard ran his veterinary practice full-time, while representing Larimer and Weld Counties in the Colorado State Senate, from 1983 to 1990. He was best known during his time in the Colorado State Senate for sponsoring the state law limiting state legislative sessions to 120 days, preserving the concept of the citizen-legislator.
Allard served in the U.S. House of Representatives from Colorado's Fourth Congressional District from 1991 to 1996, when he was elected to the United States Senate. As a Colorado Congressman, Allard served on the Joint Committee on Congressional Reform, which recommended many of the reforms included in the Contract with America. These reforms were among the first legislative items passed by the Republican controlled Congress in 1995.
Allard is currently a member of the Senate Armed Services Committee. He is Chairman of the Strategic Forces Subcommittee and a member on the Subcommittee on Emerging Threats and Capabilities and the Subcommittee On Readiness and Management Support.
He is also a member of the Senate Banking, Housing and Urban Affairs Committee, where he is the Chairman of the Housing and Transportation Subcommittee, additionally he is serving on the Subcommittee on Financial Institutions and the Subcommittee on Securities and Investments. Allard also was selected to serve on the Senate Budget Committee.
Beginning in the 108th congress Senator Allard was selected to serve on the Environment and Public Works Committee, which includes two subcommittee assignments, the Fisheries, Wildlife and Water Subcommittee and the Superfund and Waste Management Subcommittee. In January 2003, Allard accepted an assignment by Senate Majority Whip Mitch McConnell to serve as a Deputy Majority Whip. He is also the Chairman of the Senate Renewable Energy and Energy Efficiency Caucus.