Three Republican candidates are sprinting to the finish of a contentious GOP primary for the U.S. Senate, with only two weeks to go until Nebraskans cast their votes — and accusations are flying everywhere.

This week, the editor of a conservative publication accused one Republican candidate of attempting to torpedo a U.S. Senate primary opponent, potentially opening the race for another individual running in the GOP primary whom the pundit has accused of being a Democrat masquerading as a Republican.

“Shane Osborn is done in Nebraska. He cannot get the momentum to win the race. At this point, Osborn is taking the position that if he can’t win the Senate race, neither should Ben Sasse,” Red State editor Erick Erickson, who has endorsed Sasse, wrote in a Thursday blog post.

A recent poll commissioned by the Sasse campaign shows him leading the race with 31 percent of the vote, followed by Osborn at 25 percent and Sid Dinsdale with 22 percent of the vote. Those undecided account for 14 percent, and 8 percent are split between two other candidates, according to the poll.

In this March 11, 2014 photo Republican-backed Senate candidate Shane Osborn, right, and tea-party backed Ben Sasse, left, leave the stage after a debate in Omaha, Neb.  (AP Photo/Nati Harnik)

In this March 11, 2014 photo Republican-backed Senate candidate Shane Osborn, right, and Tea Party-backed Ben Sasse, left, leave the stage after a debate in Omaha, Neb. (AP Photo/Nati Harnik)

Outside observers are particularly interested in this race as it presents one of the more viable opportunities for the Tea Party to secure a significant win. The Club for Growth, Senate Conservatives Fund, Sen. Ted Cruz (R-Texas) and former Alaska Governor Sarah Palin have all endorsed Sasse.

“Osborn, who thought the race was his, is desperately upset. Joined with a Mitch McConnell Super PAC, Osborn is now throwing everything he has at Ben Sasse,” Erickson wrote.

Bill Novotny, Osborn’s campaign manager, however, dismissed allegations that their campaign isn’t serious about winning, calling them “absolutely ridiculous.”

“Osborn has consistently been number one or number two in the polls,” he told TheBlaze Saturday. “He is in this race to win it.”

When asked to respond to the allegations Erickson has made, a senior campaign adviser for Sasse confirmed that their campaign believes Osborn is merely acting as a spoiler in the primary.

“Stick a fork in Shane Osborn: he’s done,” Jordan Gehrke said in a statement to TheBlaze. “His negative attacks have rendered him a spoiler.”

“Meanwhile, Ben Sasse has not run one dime in negative ads, and has run a 100% positive campaign,” he added. “This is now a two-man race between a conservative in Ben Sasse and a moderate in Sid Dinsdale.”

Novotny fired back at the Sasse campaign, saying that “his associates in the form of Super PACs have done all of Ben’s dirty work.”

“You can’t differentiate between the negative ads they are doing versus Shane’s,” he told TheBlaze.

In his Thursday blog post, Erickson also stirred controversy when he accused the third leading candidate, Dinsdale, of being a Democrat running in the GOP primary — something Dinsdale adamantly denies.

“Waiting in the wings, with Osborn fully understanding what is happening, is Sid Dinsdale. Dinsdale is extremely rich, has a lot of money to burn at the end of the race, has benefited from sitting on the sidelines above the fray, and is a Democrat,” the Red State editor and talk show host wrote.

Erickson alleged that Dinsdale joined the race as a Republican after considering running in the Democratic primary and leveled charges against the candidate, accusing his family of working with and financially supporting pro-abortion organizations.

Republican U.S. Senate candidates, from left, Shane Osborn, Bart McLeay, Ben Sasse and Sid Dinsdale, shake hands at the University of Nebraska College of Law on Wednesday, April 9, 2014 at their final debate before the May 13 primary. (AP Photo/The Journal-Star, Francis Gardler)

Republican U.S. Senate candidates, from left, Shane Osborn, Bart McLeay, Ben Sasse and Sid Dinsdale, shake hands at the University of Nebraska College of Law on Wednesday, April 9, 2014 at their final debate before the May 13 primary. (AP Photo/The Journal-Star, Francis Gardler)

Dinsdale, a banker who has recently been rising in the race as he spends more money, denied the allegations in a press release.

“The statement in RedState.com by Ben Sasse supporter, Erick Erikson (sic) is untrue and is slanderous,” he said in the Thursday press release. “My wife Dawn and my daughters, Alison and Paige, have never been involved with Planned Parenthood and have never given money to any pro-abortion group. They have been involved in groups with the complete opposite message of Planned Parenthood such as Nebraska Children’s Home, Hope Center, Living Word Ministries, Youth For Christ and many other faith-based groups.”

“It saddens me that my wife and daughters are being subjected to attacks by groups in Washington, D.C. that have endorsed Ben Sasse,” he continued. “I am proud to be endorsed by the Nebraska Right to Life. I would never compromise on abortion and to insinuate otherwise, is nonsense.”

Dinsdale added the attacks made by Erickson are the “perfect example of the negativity that plagues our political system and continues to drive good, qualified people away from running for public office.”

Erickson, however, has not backed down. In another post, the Red State editor alleged that Dinsdale has donated to several Democratic candidates and has a history of supporting environmental activists. On Saturday, the Red State editor wrote another blog post, continuing to challenge Dinsdale’s pro-life credentials.

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