Reading the tea (party) leaves of GOP Senate primaries

Can Republicans take control of the Senate in November? And what kind of face will the party show to the voters in the future? Over the next several months, the results of primary elections will offer some clues.

There have been 25 midterm elections since the 17th Amendment transferred the choice of US senators from state legislatures to voters. In 18 of those 25 elections, the party holding the White House has suffered a net loss of seats.

Expect the upcoming general election to follow this pattern. Ironically, the Democrats' big gains in 2008 have exposed them to setbacks in 2014. They hold 21 of the 35 seats at stake this year. And seven of the 21 are from states that Mitt Romney carried in 2012. By contrast, Republicans must defend just 14 seats, only one of which (that of Susan Collins of Maine) is from a state that voted for President Obama. What's more, the president's sagging approval ratings have been a drag on Democrats in much of the country.

Senate Republicans would thus seem to have a strong chance at gaining the six seats they need for a majority in the chamber. But their task will be tougher if they drop any of the seats that they already have. They worry that some of their primaries might produce weak nominees.

Georgia on my mind

Both sides are eyeing the May 20 primary in Georgia. Incumbent Republican Sen. Saxby Chambliss is retiring, and Democrats have a formidable candidate in Michelle Nunn, a nonprofit executive and daughter of revered former Sen. Sam Nunn. Of the several Republicans vying for the GOP nomination, the one who most concerns national party officials is Rep. Paul Broun. Severely conservative, even by Georgia standards, Mr. Broun has made a series of odd statements. For instance, he has said evolution, embryology, and the big-bang theory are "lies straight from the pit of hell." Should he win the nomination, such statements would hurt him in a general election.

Another candidate, Rep. Phil Gingrey, has made gaffes of his own. One involved Missouri Republican Todd Akin's notorious 2012 claim that a woman's body could prevent pregnancy after a rape. Last January, Mr. Gingrey said that Mr. Akin was "partly right." As an obstetrician/gynecologist, Gingrey should have known better, and had to back off from the comment. Still, most experts think that he would not be quite as vulnerable as Broun in a general election.

Gaffes and opportunities

Likewise, Democrats in Iowa, Colorado, and other states are hoping for GOP nominees they can tag as extremists. They may try to nudge the process along. In the 2012 Missouri Senate race, incumbent Democratic Sen. Claire McCaskill thought that Akin would be the easiest Republican to beat. Just before the GOP primary, she ran television spots claiming that he was "too conservative." Though nominally attack ads, they were actually sly appeals for conservative GOP primary voters to back Akin. The maneuver worked. Akin got the nomination and went on to make the rape gaffe that sealed Ms. McCaskill's reelection. Look for similar tactics during the 2014 primary season.

In Kentucky, the dynamic is different. Polls show Senate Republican leader Mitch McConnell way ahead of tea party challenger Matt Bevin. For the GOP, the danger is not that Mr. Bevin would edge past Senator McConnell and lose to Alison Lundergan Grimes, a Democrat. (Actually, polls show that Bevin would not be weaker than McConnell in the fall.) Instead, Bevin's attacks are undercutting McConnell among general-election voters. McConnell was not wildly popular to begin with, and Bevin is branding him as something both parties despise: a Washington insider.

The future of the Senate – and tea party

Elsewhere, primaries likely won't shift the partisan balance but could alter the character of the Senate GOP. Mississippi Sen. Thad Cochran surprised Washington when he announced that he would seek a seventh term. Most had assumed that the 76-year-old incumbent would retire. He faces a stiff challenge from state Sen. Chris McDaniel, who has the support of the Club for Growth and other conservative groups. Mississippi has not elected a Democrat to the Senate since 1982, so either Republican would be a favorite in the fall.

The two candidates represent a choice, not an echo. The Almanac of American Politics says that Mr. Cochran "personifies a vanishing breed of southern Republican – amiable to all, conservative but not rigidly so, a devoted institutionalist, and a proficient procurer of funding for his poor, rural state." Mr. McDaniel represents a new breed: ideological and confrontational. His election would bolster hard-liners such as Sen. Ted Cruz (R) of Texas.

Old guard, fresh threats

Although not as endangered as Cochran, other old-breed Southerners, such as Sen. John Cornyn of Texas and Sen. Lamar Alexander of Tennessee, also face challenges from foes who see them as too compromising, though the two are leading their opponents for now. Sen. Lindsey Graham of South Carolina – whom Rush Limbaugh has dubbed "Lindsey Grahamnesty" for his support of immigration reform – may end up with less than 50 percent of the primary votes, and thus face a runoff. An unexpectedly close race for any of these senators would be a sign of enduring strength for the tea party.

Primaries can be unpredictable, and there could be upsets in races that aren't even on the political community's tally board. At a time when congressional deadlock is likely to drag on, the real political drama of 2014 is likely to unfold at ballot boxes this spring and summer.

John J. Pitney Jr. is the Roy P. Crocker professor of American politics at Claremont McKenna College and coauthor of "After Hope and Change: The 2012 Elections and American Politics."