Conservatives in Congress Threaten Several Programs that Chamber of Commerce Supports.

[caption id="attachment_54684" align="alignright" width="553" caption="Tea-party supporters at the fifth annual Faith & Freedom Coalition's 'Road to Majority' Policy Conference"][/caption]

Republican Sen. Thad Cochran's runoff victory Tuesday exposed the limits of tea-party power at the polls, but conservative activists retain considerable influence in Congress as they fight the Export-Import Bank, an immigration law overhaul and higher taxes to repair bridges and roads. Mr. Cochran's narrow win over a tea-party-backed challenger, coming after the defeat of conservative activists in other primary elections this year, offered further proof that GOP leaders and their business allies have built a successful strategy to nominate candidates they believe give them the best odds to win in November.

But the disconnect between tea-party election losses and the movement's continued power in Washington underscores deep divisions inside the GOP that show no sign of abating after a busy spring in which so-called establishment candidates won far more intraparty contests than they lost.

The GOP leadership, for example, benefited from millions of dollars in campaign spending by the U.S. Chamber of Commerce to promote leadership-backed candidates in nearly a dozen primaries, part of a broad effort to stem tea party momentum. And yet three of the Chamber's top legislative priorities—an overhaul of immigration law, a replenished Highway Trust Fund and reauthorization of the Export-Import Bank—are in jeopardy because of conservative resistance in Congress.

The Chamber spent $1.2 million to support Mr. Cochran in Mississippi in his victory over state Sen. Chris McDaniel, who was supported by local and national tea-party groups. Also Tuesday, national conservative groups fell short in Oklahoma, as their favored candidate lost a competitive GOP Senate primary. Both results follow similar outcomes earlier this year in Kentucky and North Carolina in which the candidates backed by tea-party activists failed to win the nomination.

GOP officials said the results didn't mark an end to the clout of tea-party activists in and out of Washington. "I'm not sure the tea party has peaked…They're still extremely viable" at a time when anger at Washington is high, said Sen. John McCain (R., Ariz.) at a breakfast Wednesday sponsored by The Wall Street Journal. Chamber officials say their goal is to elect candidates "who want to come to Washington to solve problems" not just shut down the government. "Governing is the theme we have inserted into this cycle," said Scott Reed, who advises the Chamber on strategy. "It all starts with quality candidates." Among the evidence of tea party power: Newly elevated House Majority Leader Kevin McCarthy (R., Calif.), facing the prospect that another Republican would challenge him after the November midterms, recently said he would allow the charter of the Export-Import Bank—which provides financing for the export of American goods and services—to expire, adopting a policy position championed by a more conservative potential rival, House Financial Services Chairman Jeb Hensarling (R., Texas).

Congressional conservatives also are at the center of a battle over legislation to replenish the Highway Trust Fund, which funnels federal gas-tax revenue to states to help pay for road and bridge maintenance. With a shortfall looming, House Republicans won't accept Democratic proposals to boost revenue, in an acrimonious standoff that could force states to abandon transportation projects and lay off workers. Mississippi represented the conservative insurgents' best shot at knocking off an incumbent Republican senator.

The Cochran win comes just a few weeks after conservative activists scored an upset by ousting former House Majority Leader Eric Cantor in his GOP primary in Virginia, a shocking result that scrambled the prevailing narrative that Republican leaders and their business allies were reclaiming control of their party. But tea-party activists in Virginia were quick to point out that most outside groups didn't spend money against Mr. Cantor. Conservative activists hoped that wins in Mississippi and Oklahoma would put an exclamation point on Mr. Cantor loss, reanimating the movement.

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