After the 2012 election, Reed said the chamber's leadership instructed its political operation to "get more engaged in candidate selection and primaries to identify and support House and Senate candidates that believe in growth, governing and can win in November."

Senate or U.S. House candidates aligned with the Tea Party lost yesterday in Georgia, Kentucky, Pennsylvania and Idaho. Those contests were widely viewed as this year's pinnacle in the intraparty fight.

Economic agenda

Besides selecting candidates with a better chance of winning in November, the business-backed coalition is also seeking to boost candidates who are more steeped in and supportive of an economic agenda, including ensuring that the nation doesn't default on its debt.

Nominating the strongest candidates is essential because there's little room for error, if Republicans are to secure the net gain of six seats they need to win control of the Senate.

"So far, Republicans are getting the candidates they want for the general election," said Jennifer Duffy, who studies Senate races as a senior editor for the nonpartisan Cook Political Report in Washington. "It was not a good night for the Tea Party."

The power struggle hasn't been a total loss for the small- government movement spawned in part by protests to passage of the Affordable Care Act in early 2010.

While Tea Party aligned candidates have lost individual races this primary season, they have in some cases pushed the winning Republicans to positions that will be used against them by Democrats in the November election.

Climate change

Ahead of his May 6 primary win, Republican Senate nominee and North Carolina House Speaker Thom Tillis joined his primary rivals in saying climate change isn't an established fact.

"When the establishment runs on our issues, it's clear that there is a larger cultural shift happening here," Matt Kibbe, president of Washington-based, small-government advocate FreedomWorks, said in a statement. "Constitutional conservatives and libertarians are setting the agenda in the Republican Party."

Still, the movement has had scant opportunities to celebrate during a primary season in which incumbent Republicans were on alert and better prepared for challengers.

The movement's highest-profile target, Senate Minority Leader Mitch McConnell, 72, easily defeated Matt Bevin, a businessman aligned with the Tea Party, in Kentucky's Republican primary yesterday. With all precincts reporting, McConnell had 60 percent of the vote to Bevin's 35 percent in the five- candidate race.

November challenge

McConnell's bid to secure a sixth term will get considerably harder. In November, he'll face Democratic Secretary of State Alison Lundergan Grimes, 35, who easily won her party's nomination. The Cook Political Report rates their race as a "tossup."

In Idaho, U.S. Representative Mike Simpson, an Appropriations subcommittee chairman and ally of House Speaker John Boehner, survived a Republican primary challenge from Tea Party-aligned Bryan Smith, a lawyer and political novice. With 99 percent of precincts reporting, Simpson had 62 percent of the vote, Smith 38 percent, according to the Associated Press tally.

The threat to Simpson, 63, had awakened local business groups and Idaho companies with little or no history of getting involved in primaries. The U.S. Chamber of Commerce listed his protection as one of its top 2014 election goals.

Bailout vote

Simpson, seeking a ninth term, angered Tea Party activists as the only member of the current Idaho congressional delegation in 2008 to back the $700 billion bailout of financial markets. He also was one of just 16 House Republicans in March 2012 to support a budget plan that would have raised revenue as well as cut spending.

In Pennsylvania's most heavily Republican district, House transportation leader Bill Shuster yesterday fended off a Tea Party challenger who had attacked him as a big spender behind some of Congress's priciest infrastructure bills.

The movement also wound up being shut out in a crowded Senate primary in Georgia, where two of the Republicans seeking the nomination will face off in a July 22 runoff after none of the seven candidates topped the required 50 percent of the vote.

David Perdue, a former chief executive officer of Dollar General Corp. and Reebok International Ltd., and U.S. Representative Jack Kingston will compete in the runoff for the right to go against Democrat Michelle Nunn, who easily won her party's nomination against three opponents.

Georgia runoff

The two Republicans will spend two months competing against each other in what promises to be a tough and expensive campaign, instead of focusing their fire on the daughter of former Democratic U.S. Senator Sam Nunn of Georgia.

Democrats would have preferred to face a candidate aligned with the Tea Party, which would provide a greater contrast for Nunn, 47, to appeal to independent voters. All three of those candidates — Representatives Phil Gingrey and Paul Broun and former Georgia Secretary of State Karen Handel, who was backed by former Alaska Governor Sarah Palin — were defeated in the primary.

Perdue, 64, has stressed his credentials as a businessman and Kingston, 59, has a profile that clashes with the type of candidate Tea Party supporters gravitate toward: He's been in the House since 1993, won millions of dollars for the now-banned home-state spending projects known as earmarks, and is a prodigious fundraiser with strong corporate ties.

With 99 percent of precincts reporting, Perdue had 31 percent of the vote, according to the AP tally. Kingston had 26 percent.

If Republicans do gain momentum this election year, they may expand their targeted Senate races to include first-term Democrat Jeff Merkley in Oregon, a state President Barack Obama won by 12 percentage points in 2012. In November, Merkley will face pediatric neurosurgeon Monica Wehby, who won the Republican primary.

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