A Democrat hasn's been elected to Congress from Wyoming in 35 years. I don't see that changing regardless of who wins the nomination.
Never say never. WY Democrats came VERY close to knocking off Rep. Barbara Cubin in 2006 (1,000 vote margin). The advantage Democrats have is that they can conceivably win ANY House seat in the nation under the right circumstances (they have done so in Utah, as an example). Republicans cannot, as there are perhaps 100-150 House seats that have a racial and/or ideological barrier.