(Getty Images | Shannon for Senate)

Rep. James Lankford won the seven-candidate Republican primary in the Oklahoma Senate race to replace the outgoing Sen. Tom Coburn Tuesday, avoiding a runoff and defeating a tough, tea-party funded challenger.

In a setback for national tea party forces, Lankford, a rising GOP star in Washington, defeated T.W. Shannon, the African-American and Native American former speaker of Oklahoma's House of Representatives who received endorsements from Sarah Palin and Sen. Ted Cruz, R-Texas. He too is considered a rising star within the party.

With 76 percent of precincts reporting, Lankford received 56 percent of the vote to Shannon's 35 percent, according to the Associated Press.

"Lankford's demonstrated broad appeal we haven't seen from an Oklahoma City-based candidate in 50 years, so it's an exceptional victory," said Keith Gaddie, a University of Oklahoma political science professor.

The two-term congressman, 46, will likely win the general election in deep-red Oklahoma, where Republicans hold every statewide office and both state legislative chambers.

In a primary cycle defined by intense and vicious contests between tea party and establishment candidates, both Lankford and Shannon could claim GOP bona fides and grassroots support.

Lankford currently serves as chairman of the House Republican Policy Committee, a high-level position in the caucus; Shannon, the current speaker of the Oklahoma House, has worked for members of the Oklahoman delegation: Current Rep. Tom Cole, R-Oklahoma, and former Congressman J.C. Watts.

A director of the country's largest Baptist youth camp before becoming a politician, Lankford rode into Washington on the 2010 tea party wave and the support of religious conservatives. But his vote to raise the debt ceiling and association with House leadership led to attacks on his right flank.

National groups such as Freedomworks and the Senate Conservatives Fund lined up to support Shannon, and both Palin and Cruz campaigned for him.

One endorsement missing from the race was Coburn's. While the senator defended both candidates from attack ads, his defense of Lankford's record, two weeks before the primary, "came as close to endorsing as you possibly can," said Gaddie.

"When Coburn makes his way into a primary, it usually makes a difference to people," Gaddie said of the state's popular junior senator, who is battling cancer.

While Shannon, 36, stepped down from his position in the state legislature to run for Senate, Oklahoma state observers believe the loss won't be end for the "striking" young Republican.

"I don't think his political career on the national stage is over," said Mike McCarville, an Oklahoma political blogger.