In more than a dozen states, House and Senate primary elections will happen on the same ballot with the presidential race — timing that could pose a challenge for incumbent candidates in intra-party battles.  

Presidential candidates such as New York City real estate mogul Donald Trump and Texas Sen. Ted Cruz are hoping to lure new, anti-establishment voters to the polls, a change that would skew the kinds of voters candidates will face.  “The S.E.C. states,” said Midwest-based Republican consultant James Harris, using the nickname for the group of southern states that share the March 1 primary date, “will have an uptick in their normal turnout because of the presidential primaries.”  

“Trump and Cruz? They could bring out new people, and they’re using messaging that helps challengers,” he added.  

One of those early states is Alabama, where Harris is helping ex-Marine Jonathan McConnell, one of the four Republicans running against Sen. Richard C. Shelby in the primary. With the totals of Trump and Cruz combined, Harris said about 67 percent of primary voters are so far aligning with the candidates viewed as anti-establishment. To avoid an April run-off, Shelby needs a majority of those voters to be with him, too.  

Shelby backers insist the fifth-term Republican is not worried. He chairs the powerful Senate committee that oversees banking, and had about $19 million in his campaign account as of Sept. 30. But, his campaign announced last week that it would spend $6 million of that on a television advertising campaign through primary day.  

Richard Fording, chairman of the department of political science at the University of Alabama, said “barring a major scandal or something catastrophic,” he thinks Shelby will be fine in his re-election effort. Still, he said anti-establishment energy by voters could come to play further down the Republican primary ballot in his state, where Rep. Martha Roby is facing opposition by Becky Gerritson the leader of the Wetumpka, Ala., tea party group.  

“Although Roby was elected in the 2010 midterm during the peak of the tea party movement, she has a reputation for being one of the more moderate members of Alabama’s Republican House delegation,” Fording said, voting with House Republican leadership on spending bills controversial to parts of the party’s base. There, Gerritson has found an opening. She has already taken to social media to criticize “the Washington cartel,” an anti-establishment phrase made famous by Cruz.  

“I think that we could see an unusually large primary turnout due to the number of Republican candidates competing and the ‘Trump’ factor, which will undoubtedly mobilize a lot of Republicans on the far right — Gerritson’s crowd,” Fording said.  

In all of these states, the known unknown is whether the people telling pollsters they are mad at the establishment will actually show up.  

“Trump has put together a group of voters who feel disaffected and are angry at Washington. The big questions are, will their anger translate into votes, and will they participate in the political process they hate beyond watching him on TV,” said Ron Bonjean, who has worked on top Senate races in the past. “Nobody knows the answer.”  

The Republican presidential race — with its large number of candidates — might drag on for some time before the Republican national convention in the third week of July. So the month of March, during which 59 percent of the delegates will be decided, will be important. By the end of that month, 64 percent of the delegates will have been decided, a Republican National Committee official said.  

Prior to March 14, delegates must be committed proportionately unless they reach a certain, state-selected threshold — a rule that could help a lower-performing candidate limp along and drag out the nominating contest.  

Because of that, a similar dynamic to the one in Alabama could play out just two weeks later in North Carolina. In that March 15 primary, Republican Rep. Renee Ellmers faces conservative challenger Jim Duncan in the 2nd district. Both the more moderate Main Street Partnership backing Ellmers and the conservative Club for Growth supporting Duncan are playing there in what could be one of the year’s most contested primaries.  

For incumbents considered not conservative enough for the base, Bonjean said, “Some of these races will stay local, but it does not help when you have a very conservative presidential candidate that is leading a state.”  

The primary election problem may not be exclusive to the Republican establishment. If the Democratic race drags out between former Secretary of State Hillary Clinton and Vermont Sen. Bernard Sanders, March 15 is a primary date to watch in Ohio and Illinois, where establishment-backed Democrats are facing challengers for Senate nominations ahead of two marquee races in November.  

In Arizona, Republican Sen. John McCain has a different, less predictable challenge. There, primary voters will make their presidential pick on March 22 — more than five months before he will face his primary challenger, former state Sen. Kelli Ward, in the August 30 primary.  

An operative supporting McCain said that without the entrance of a more heavy-hitting primary challenger, such as Rep. David Schweikert, who remains undecided on whether to run, his challenge will be turning out supporters in the heat of the Arizona summer. “It’s really hot in Arizona in August, and early voting becomes a big deal,” the operative said.  

By the time McCain is on the primary ballot, Harris, the Midwest Republican consultant, said perhaps the party will have let off its steam during the Republican convention. “If I’m McCain, I’m hoping the anti-establishment tsunami slows down.”

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