The battle for endorsement in the race for Nevada open U.S. Senate seat is heating up.

On Wednesday, Democratic candidate Catherine Cortez Masto was in town for the announcement of an endorsement from the Police Officers Research Association of Nevada. It's a 10,000 member group. 

"We did extensive interviews with all of the candidates," said Ron Drehr. "We took a lot into consideration. And we feel that Catherine Cortez Masto will better represent us in Washington. She understands the law enforcement community and will fight for us."

Republican candidate Joe Heck was quick to point out that the 10,000 member number is the entire membership of the group and does not necessarily mean all those members will support her in the voting booth. He also gave a list of his own supporters. 

"For that group of unions to endorse her really is figureheads supporting her. We have rank and file. We have the current Attorney General Adam Laxalt, 14 sitting County Sheriffs in the state and 10 of the state's District Attorneys. And the list of supporters from law enforcement is growing by the day." 

Masto is confident with the race saying her biggest focus will be the frustration voters have with those already in Washington.

"I want to represent the people of Nevada and the issues here that impact families her.e. And my record shows I can do that."

There are four other candidates in that race. Tom Jones is running as an Independent American Party Candidate. Tony Gumina, Tom Sawyer and Jarrod Williams are all running as non-political party candidates.