By John Whitesides
WASHINGTON (Reuters) - A North Carolina Republican backed by the party establishment fought off Tea Party and Christian conservative rivals on Tuesday to win the nomination to take on vulnerable Democratic Senator Kay Hagan in November.
State House Speaker Thom Tillis was projected to capture more than 40 percent of the vote, surpassing the amount needed to avoid a costly July runoff with the second-place finisher.
Tillis's victory sets up a general election fight with Hagan that will be among the country's most hard-fought and closely watched U.S. Senate races. Republicans must pick up six seats to win a Senate majority.
With about 90 percent of the vote counted, Tillis had 45 percent to Tea Party favorite Greg Brannon's 27 percent and 18 percent for evangelical minister Mark Harris.
The Republican Senate primary in North Carolina was the first in a string of nominating battles - including May 20 contests in Kentucky, Georgia and Oregon - that will begin to determine the success of the party establishment's effort to beat back the conservative Tea Party movement and recapture the Senate majority that eluded it in 2010 and 2012.
Tillis, who described himself as a fiscal and social conservative, was helped by more than $2.6 million in advertising from two powerful outside advocacy groups - the business-friendly Chamber of Commerce and American Crossroads, founded by strategist Karl Rove.
The North Carolina race also attracted a flood of endorsements from high-profile outsiders. Tillis gained the backing of 2012 presidential nominee Mitt Romney and former Florida Governor Jeb Bush, while Brannon was joined for a campaign stop on Monday by Kentucky Senator Rand Paul, and Harris won the backing of former Arkansas Governor Mike Huckabee.
Tillis, speaking to a jubilant crowd of supporters in Charlotte, was quick to link Hagan with President Barack Obama and Democratic Senate leader Harry Reid.
"She will walk through the fire for President Obama even though she knows his policies are a failure," he said. "Let's sweep Kay Hagan out of office and let's sweep Harry Reid to the back row."
Hagan said in a statement that Tillis's conservative record of cutting public education and supporting tax cuts for the wealthy was "out of sync" with North Carolina values.
"The election is a simple choice between two very different records," she said.
In other North Carolina primaries, former "American Idol" TV show runner-up Clay Aiken was in a tight race with former state Commerce Secretary Keith Crisco for the Democratic nomination to challenge Republican Representative Renee Ellmers.
Republican Representative Walter Jones, known for his vocal opposition to the Iraq war, defeated challenger Tyler Griffin, a political consultant.
While North Carolina grabbed the spotlight on Tuesday, voters in Indiana and Ohio also chose candidates for November.
In Ohio, Democrats nominated Ed FitzGerald, a former FBI agent and now Cuyahoga County executive, over minor opposition to take on Republican Governor John Kasich in what will be one of the top governor's races in November.
(Additional reporting by Colleen Jenkins in North Carolina; Editing by Ken Wills)