Sen. Rand Paul, R-Ky., offered an endorsement on Wednesday to a tea party activist running for the GOP Senate nomination in North Carolina — a top pickup opportunity for Republicans.

Physician Greg Brannon, one of several Republicans vying to take on Democratic Sen. Kay Hagan, touted the endorsement from the conservative senator and potential presidential contender as a momentum boost for the campaign. The campaign’s announcement referred to Brannon as “an anti-establishment candidate … who will oppose the Big Government, big spending status quo in both parties.”

In a statement, Paul called Brannon “a true constitutional conservative who will join me in fighting against business as usual in Washington.”

“I urge conservatives in the state of North Carolina and across the nation to rally around Greg Brannon by contributing generously to his campaign and joining the grassroots volunteer effort to ensure that there is a strong Constitutional conservative Senator from North Carolina,” Paul said.

According to Brannon campaign manager Reilly O’Neal, Brannon raised about $155,000 over the last three months and ended the quarter with $105,000 in cash on hand. Those numbers could receive a boost with Paul’s backing.

There are at least half a dozen candidates in the GOP primary, including state Speaker Thom Tillis and the Rev. Mark Harris. They all start off behind financially to Hagan, who reported raising $1.8 million in the third quarter and had $5.4 million in cash on hand as of Sept. 30.

The race is rated Tossup/Tilt-Democrat by Rothenberg Political Report/Roll Call.

Paul’s father, former Rep. Ron Paul, R-Texas, recently endorsed in the Colorado Senate race, where an increasingly crowded GOP primary will decide who takes on Democratic Sen. Mark Udall. The elder Paul backed state Sen. Owen Hill, who he said “can be counted on to work for limited government and more personal liberties.”