05/14/2012 05:00 pm ET

Richard Mourdock: I Didn't Endorse Herman Cain's '9-9-9' Plan

Indiana State Treasurer Richard Mourdock got some props last week from Herman Cain, who congratulated Mourdock both for winning the Republican primary for U.S. Senate and for adopting Cain's 9-9-9 tax plan.

“We the People have just taken a huge step forward in the mission to get our power back from the clutches of Washington, D.C.,” Cain said in a press release. “By adopting my 9-9-9 plan, Richard Mourdock has shown he is committed to simple, common sense solutions to the nation’s biggest problems. I am proud the voters recognized this as well."

Only problem -- Mourdock's campaign says he never actually endorsed Cain's plan.

“Richard Mourdock does believe that we need a major change in the federal tax code, which makes it flatter, fairer and broader,” Mourdock spokesman Chris Conner told ABC News. ”Our campaign, however, did not officially endorse Herman Cain’s 9-9-9 Tax Plan.”

That was apparently good enough for Cain's campaign, which refers to Mourdock as a "Cain ‘Lieutenant.'" Caine was "thrilled," that Mourdock was willing to even bring up 9-9-9 as part of the debate on tax codes, spokeswoman Kathy Hoekstra told ABC.

Cain's proposed tax plan would create a flat 9 percent income tax, business tax and national sales tax. He also touts the support of several other U.S. Senate candidates, including former Rep. Pete Hoekstra (R-Mich).

Mourdock, whom Cain endorsed in August, won a resounding victory in his primary last week against incumbent Sen. Richard Lugar (R-Ind). He will face Rep. Joe Donnelly (D-Ind.) in November. A Democratic poll released Monday said the two tied at 40 percent.

10 more election stories from beyond the presidential field:

Rick Perry Supports Lt. Gov David Dewhurst In Radio Ad [Texas Tribune]

Nebraska Senate Race Is Down To The Wire [Omaha World-Herald]

Scott Brown Again Calls On Elizabeth Warren To Release Documents [Boston Herald]

No GOP Endorsements In Wisconsin Senate Race [Milwaukee Journal-Sentinel]

Primary Will Test California's New Voting System [Los Angeles Times]

Texas Primary Full Of Challengers To Incumbents [Houston Chronicle]

Rhode Island's Gov. Lincoln Chafee To Get Challenge In 2014 [WPRI]

Connie Mack Fires Back At George LeMieux Over Residency, Law Firm [Orlando Sentinel]

Washington Gov. Gregoire Emerges As Unlikely Gay Rights Activist [KPIU]

Chris Murphy Forced Into Primary In Connecticut [Patch]