In Wyoming, Barbara Cubin is widely perceived as being an ineffective gadfly who has accomplished very little. Her attendance record has come under criticism a number of times. The fact that she didn't run for an open U.S. Senate seat in 1996 was an indication of political weakness (historically, At-Large Congress members in Wyoming always run for the Senate sooner or later).
It would not have been smart for her to run for the Senate after only a single term in the House, since when two other former members attempted that, they both lost (Teno Roncalio in 1966, John Wold in 1970 -- even William Henry Harrison, IV, ran in 1954 after 2 terms and lost). Usually a minimum of 3 terms would be the prerequisite in Wyoming for the House member.