McDaniel’s campaign has challenged that edifice of party orthodoxy. A confrontational conservative who made a name for himself as a sharp-elbowed member of the Legislature, McDaniel has been surrounded in his race by a throng of ideological fellow travelers in the state Senate. They ride on his campaign bus and speak at his rallies. Like McDaniel, they have campaigned against the establishment in Jackson and enjoy support of the tea party — and they may set their sights on higher office as early as next year.

Win or lose this week, conservatives here predict that Mississippi’s state elections in 2015 will bring another reckoning for the party. The reality that McDaniel has come so close to unseating Cochran may herald a larger-scale shift in culture for a state where seniority has long been king.

The brimming activist rage over Cochran’s efforts to win Democratic crossover votes this week has added an extra shot of determination to the insurgents’ efforts. Feeling that they have been opposed at every turn by power brokers in Jackson, including every major sitting GOP official in the state, they are looking to the 2015 elections as the next chance to upend state politics.