How Are U.S. Senate Vacancies Filled?

This is useful background information for future reference.

 

Among the 46 states that do give their governors authority to name replacement senators, 11 limit their field of choice in some way. 

Seven states – Hawaii, Kentucky, Maryland, Montana, North Carolina, West Virginia and Wyoming – make the governor choose from a list of nominees submitted by the previous senator’s party. (Kentucky joined that group last year, at the urging of Republican Sen. Mitch McConnell, age 80; perhaps coincidentally, Kentucky Gov. Andy Beshear is a Democrat.) 

Utah requires the governor to choose from a list of candidates compiled by the legislature, all of whom must be of the same party as the previous senator. 

Arizona and Oklahoma simply require the governor to choose someone from the previous senator’s party.

Connecticut has the most restrictive rules: The governor can fill a Senate vacancy only if there’s a year or less remaining in the term, and his or her choice must be approved by a two-thirds vote in each house of the state legislature.

The 17th Amendment also gives states considerable leeway in deciding how long temporary senators can serve until a special election. In 30 states, special Senate elections must be held concurrently with regular general elections. In some cases, those special elections coincide with the next scheduled general election, but in other cases – especially if the vacancy occurs late in the election cycle – they coincide with the general election after the next one.

Five states have specific timetables for holding special Senate elections, usually a certain number of days following the occurrence of the vacancy. Thirteen states authorize either a separate date for the special election or hold it concurrently with the next general election, depending on when the vacancy occurs. And two states have few or no rules on when a special election must be held, effectively leaving the decision up to the governor.

From Pew.