Indiana State Treasurer Richard Mourdock (R) is confident that he'll beat six-term Sen. Richard Lugar (R) in their primary next Tuesday.

Mourdock, a long-distance runner, compared the campaign to the Boston Marathon, saying he felt he was in the final downhill stretch.

"We've crossed our great hill. It's all downhill from here, but we know that if you stop running even downhill you cramp up," he told The Hill on Monday. "I'm confident but I'm not cocky."

There are many signs Mourdock has edged past Lugar, foremost the decision by the American Action Network to stop spending on Lugar's behalf in the race. 

The Tea Party-backed Mourdock, who has had a lot of support from outside groups in the race, said he embraced the movement's ideals but took a shot at Nevada's Sharron Angle and Delaware's Christine O'Donnell, both failed Tea Party Senate candidates in 2010. 

"Am I a Tea Party guy in terms of wanting more constitutional values, and in terms of having more conservative views than Mr. Lugar? You bet. But this isn't like Nevada or Delaware, people tell me, they see something there," he said. "I know the policies inside and out."

Some Democrats have predicted a Mourdock primary win could put the seat in play, and a nonpartisan poll of the primary conducted in early April showed nearly half of Lugar's supporters were undecided on who they would vote for in the general election or planned to vote for Rep. Joe DonnellyJoseph (Joe) Simon DonnellyDemocrats now attack internet rules they once embraced Dem group launches M ad buy to boost vulnerable senators Senate rejects Trump immigration plan MORE (D-Ind.). But Mourdock was similarly confident he'll win the general election.

"I have two words: Bring it," he said, and compared Donnelly to former Rep. Brad Ellsworth (D-Ind.), a Democrat with a similarly centrist record who lost his 2010 Senate race by 15 points. "We're going to have a very strong presidential ticket, and we're going to win."