( CNN ) -- The midterm elections are around the corner . The big question will obviously be what happens to control of the House and Senate . But control of Congress is only one part of the equation . There are a series of issues that will shape the individual races that will tell us a lot about which way American politics is heading . Can mainstream Republicans take the party back ? There are a number of House and Senate primaries where Republicans , organized through business-backed organizations , are trying to seize back control of their party . Former Ohio Rep. Steven LaTourette and the Main Street Partnership , a group with strong backing from the corporate world , are trying to counteract the power of the tea party , which they believe is damaging the standing of the GOP . `` We want our party back , '' LaTourette explained to the The New York Times . In the 2nd District of Idaho , Rep. Mike Simpson is facing a strong challenge in the May primaries from Bryan Smith , a tea party Republican who has received support from the Club for Growth . Smith is challenging the eight-term incumbent by depicting him as an embodiment of Washington Republicans who refuse to stand firm for real budget cuts , a legislator who agreed to reopen the federal government even without what conservatives would consider a good budget deal . The Main Street Partnership has been fighting back . The most visible battle between a mainstream Republican and tea party Republican is taking place in Kentucky , where Senate Minority Leader Mitch McConnell is facing a challenge from Matt Bevin in the primary . In Texas , the controversial right-wing Rep. Steve Stockman is running against Sen. John Cornyn . Can Democrats take advantage of Republican problems ? Despite the fallout from the rollout of the Affordable Care Act , Democrats are hoping that they can take advantage of the turmoil facing the Republicans over the recent year , as the party 's approval ratings have plummeted in light of the budget battles and the public 's unhappiness with the party 's growing extremism . There are certain must-wins for Democrats if they are to show that they are capable of taking advantage of this moment . In Florida 's 13th District , Alex Sink , a well-known and well-respected Democrat , is attempting to win the seat of long-term Republican veteran Bill Young , who recently died , leaving open this highly competitive district . If Democrats ca n't win this special election on March 11 , it will signal trouble . Democrats will also be looking for a win in Florida 's 2nd District , where Gwen Graham is trying to defeat Rep. Steve Southerland in a test of whether the South has really softened as conservative territory . The Democratic Congressional Campaign Committee has been pouring resources into the district to paint Southerland as a poster child for the House GOP . `` Congressman Southerland 's reckless plan to repeal the entire Affordable Care Act would mean 614,200 consumers in Florida would be left without health insurance rebates , '' said one party spokesperson . What effect will the politics of immigration have ? After the 2012 election , many experts predicted that the immigrant vote would continue to flow toward the Democrats while Republicans will pay the electoral price for their obstruction . Now we 'll find out if that 's correct . In Colorado 's 6th District , Republican Mike Coffman , a former opponent of immigration reform who changed his tune after redistricting brought an infusion of Latinos into his constituency , is struggling to hold on to his seat . Democrats are hoping that the sizable Hispanic population in suburban Denver will demonstrate their opposition to what the House Republicans have been doing by blocking legislation that would offer a path to citizenship . Which is the more politically potent issue -- opposing Obamacare or supporting the minimum wage ? Both parties are putting forth national issues for candidates to run with in their districts and states . Democrats are honing in on the issue of economic inequality , stressing their campaign to raise the minimum wage from $ 7.25 to over $ 10 by 2015 . For Democrats , the risk is alienating Democrats from centrist constituencies who believe this will damage the economy . But they hope that the strong support in polls for the minimum wage boosts their candidates . Rep. Steve Israel , chair of the Democratic Congressional Campaign Committee , predicts that there are at least 12 seats where labor-based campaigns to raise the minimum wage will help Democrats . `` The refusal to increase the minimum wage is just one of the ways House Republicans have inflicted harm on the economy and hurt people 's pocketbooks , '' Israel said . For Republicans , the risk is they will be perceived as a party that is stuck in the mud , at a time that millions of Americans are starting to finally see benefits from the ACA rather than simply see the program as something abstract that threatens their families . In Arkansas , Republicans are counting on Sen. Mark Pryor 's support for the Affordable Care Act as a useful target for Rep. Tom Cotton to unseat this incumbent . Republicans will do the same in Louisiana , where Sen. Mary Landrieu has a record of statements in support of the health care program . How much money should we spend on elections -- and where should it come from ? This is the question now asked of every congressional and presidential election , but it is one we need to continue asking . On both sides -- the U.S. Chamber of Commerce , Freedom Works , Club for Growth , and America Rising on the right and American Bridge and Priorities USA on the left -- independent organizations are ready to roll in an unprecedented effort . With each election we have been seeing the cost of campaigning rise and the need for candidates to court donors as more and more urgent . The Kentucky Senate race will probably be the most expensive ever . All of this fuels the power of private money in our political system , undermining trust in government and supporting gridlock . When the results become clear in November , we will know a lot more about the general tenor of the American electorate . Politicians in both parties will have a better read of the kind of electorate they will be facing as they move into the 2016 presidential election . The opinions expressed in this commentary are solely those of Julian Zelizer .
As 2014 elections loom , there are questions beyond which party controls Congress . Julian Zelizer asks whether mainstream GOP can overcome tea party direction . He says which argument is stronger : against Obamacare , or for minimum wage hike ? Zelizer : What impact will the politics of immigration reform have on the result ?