(CNN) -- While America faces many big issues -- unrest in the Middle East, the effects of climate change, uneven economic growth, growing income inequality, a costly and less than optimal health care system and more -- the contest to control the House and Senate does not really seem to be turning into a defining struggle over the national agenda. Clearly the 2014 midterm elections aren't generating much excitement on the hustings. According to Gallup, voter enthusiasm is down significantly since 2010. Republicans are more enthused than Democrats, according to Gallup, but neither party is doing very well. Given that many of the key races in competitive states might come down to a small percentage of voters, as is usually the case in midterms, enthusiasm and its impact on turnout can be decisive on Election Day.
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Polls show voters are not caught up in the election, with Democrats even less enthusiastic
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Julian Zelizer says GOP voters must deal with split between moderates and tea party faction
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Democrats are struggling with how to dissociate themselves from unpopular Obama policies, he says
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Zelizer: Candidates for 2016 have to decide how to try to transcend these struggles
@placeholder candidates are struggling to figure out how far they need to go in disassociating themselves with the president of their own party.