Senator Craig Thomas succumbed to leukemia last night, and our thoughts and prayers are with his family at this trying time, but his passing helps underline the need for a major change, most likely brought about by a Constutional Amendment, in the way vacancies in the House and Senate are dealt with.
Under the current law, the Governor of each State nominates a replacement Senator upon the death or resignation of one of that State's Senators. In Senator Thomas' case, this will not affect the balance of power since Wyoming's laws require his replacement to be chosen from the same party. However, in many other cases this has not been the case.
In 1982, when Democrat "Pete" Williams of New Jersey resigned in disgrace after his ABSCAM conviction, Republican Governor Tom Kean replaced him with Republican Nicholas Brady (who would later serve as Treasury Secretary).
Pennsylvania Republican John Heinz' death in a helicopter accident in 1991 led to Governor Bob Casey replacing Heinz with Harris Wofford, who then won a special election to finish out the term in his own right.
After the death of Paul Wellstone, Reform Party Governor Jesse Ventura of Minnesota replaced him with Dean Barkley, who had received 7% of the vote against Wellstone in 1996 when he ran on the Reform party line. Barkley only served for a short period, until Norm Coleman defeated former Senator and Vice-President Walter Mondale in the November 2002 election.
Had the law in Wyoming been different, the Democratic Governor would be appointing a Democrat to the seat, effectively (as was the case in the three examples above) overruling the decision of the state's voters, who overwhelmingly re-elected Thomas last year. Similarly, the death of a Democratic Senator in any State with a Republican Governor would lead to the Republicans retaking the U.S. Senate. The illness of Senator Tim Johnson of South Dakota (whose Republican governor has stated he would appoint a Republican if Johnson resigns or dies) also underlines the need to change the way we replace Senators.
The Constitution needs to be amended, providing for the direct election of a replacement Senator by the people of a State within 60 days of a vacancy. This decision needs to be taken out of the hands of Governors, and handed over to the voters, to let them decide for themselves who will fill the Senate's empty chair.