The Mississippi GOP could be a victim of its own success in local races. 

As a result of the municipal elections last week, a total of three special elections are likely in the House over the next few months. A loss in one could send the Republican supermajority into the history books in Mississippi. 
Special elections are non-partisan, however, candidates usually let it be known as to where they align on policy matters and what side of the aisle they plan to caucus with once elected.  Plus, if you follow the money and endorsements it’s not that difficult to figure out. 
In Pearl River County, the House District 108 seat has a July 25 date set for its special election to replace Mark Formby, a 24 year member of the lower chamber who was appointed to serve on the Worker’s Compensation Commission by Gov. Phil Bryant. 
Formby soundly won reelection over Democrat Leavern Guy 77% to 23% in 2015.  
The population make up in HD 108 tends to be tailor-made for conservatives, leaving no reason to believe Republicans will not hold on to this seat. 

Two other vacancies will set up special elections this fall following last Tuesday’s municipal election results. 
The PineBelt’s House District 102 seat currently held by Hattiesburg Mayor-Elect Toby Barker is one to watch.  
Barker has been able to hold this seat amid shifting demographics, meaning that while he has won the last two legislative elections by 65% or higher over Democrat challengers, HD 102 has a population that could give a Democrat a decent shot with Barker not on the ballot.

In Warren County, the House District 54 seat will be vacated after Alex Monsour’s South Ward Alderman win in Vicksburg.   
Given the population of the district and that Monsour has largely been unopposed during his terms (2 out of 3 times), Republicans should feel confident in keeping HD 54 but they cannot phone this one in and expect to win. 

As disjointed as Democrats have been on a statewide level, Republicans should be well aware that there will be a fight.  Recruiting good candidates who are adequately funded and well staffed will mean everything to both sides. 
And if HD 102 does somehow go blue, expect a push by House leadership to bring a sitting Democrat over into the fold so Republicans can remain with the coveted 74 seats. 
Regardless, this should be a wakeup call for Republicans in the Mississippi legislature that nothing lasts forever.  Supermajorities are indeed perishable and kicking the can down the road on major items can come back to bite you.