WASHINGTON - Indiana Gov. Mitch Daniels has made a splash by jumping into the state’s hotly contested Republican Senate primary with both feet, cutting a recent television ad in which he gives a ringing endorsement of incumbent Sen. Richard Lugar.
    
In Washington, there’s more reticence about the fierce battle between Lugar and state treasurer Richard Mourdock. The Hoosier congressional delegation is staying out of the water.
    
The lawmakers say they don’t want to get in the way of voters.
    
Rep. Todd Young (R-9th CD) follows what an aide calls the “Dan Quayle rule” - named after the state’s former U.S. senator and vice president.
    
“Congressman Young thinks that as a Republican primary voter, his vote shouldn’t count as more important than anyone else’s,” said spokesman Trevor Foughty. “We have not gotten involved in any race – from the local up to the party level, including the Senate race.”
    
In southwest Indiana, Rep. Larry Bucshon (R-8th CD) faces a primary challenge on the right from Kristi Risk. Like Bucshon, Mourdock is from the Evansville area. But their similar geography hasn’t prompted Bucshon to weigh in for Mourdock.
    
“He’s going to stay neutral in the Senate primary,” said Bucshon spokesman Matthew Ballard. “The congressman is focusing on his own race and trusts Hoosier voters to make the right decision.”
    
Rep. Marlin Stutzman (R-4th CD) joined Lugar in introducing Rural Economic Farm and Ranch Sustainability and Hunger (REFRESH) Act last fall. The measure would save an estimated $40 billion in agriculture spending over 10 years and usher in other reforms. It is part of the mix as Congress works on a new farm bill this spring.
    
Despite the legislative cooperation, Stutzman is not getting involved in the Senate primary.
    
“No, I do not have plans to endorse either candidate,” Stutzman said in an email statement. “I am comfortable letting the voters decide the outcome of the election."
    
Lugar’s Republican Senate colleague, Dan Coats, is staying on the sidelines, too.
    
“Senator Coats has taken the position of not endorsing primary candidates and is leaving that decision to the voters of Indiana,” communications director Tara DiJulio wrote in an email.
    
In the highest profile endorsement of the race, Daniels is trying to shape voters’ opinions. “I’m not for Dick Lugar for what he’s done but for what he can do,” Daniels says in his television ad. “Our point of view gets heard and has a better chance to win out with Dick Lugar on the job.”
    
Lt. Gov. Becky Skillman, former Secretary of State Condoleezza Rice, a majority of Hoosier mayors and the Hamilton County GOP are among the others who have endorsed Lugar.
    
Mourdock has been endorsed by former GOP presidential candidate Herman Cain, 55 Hoosier tea party groups, billionaire publisher Steve Forbes and many county chairmen.
    
Washington lawmakers, however, don’t want to talk about the Senate primary.
    
“I don’t have anything for you on that,” said Josh Britton, spokesman for Rep. Todd Rokita (4th CD). Rokita is not making an endorsement.

Schoeff is HPI's Washington correspondent.