In a statement, U.S. Sen. Dan Coats, R-In., congratulated Republican Senate candidate Richard Mourdock in his blowout victory over incumbent Dick Lugar in the GOP primary.The state treasurer defeated the six-term Senator by a 20-point margin and ended one of the largest Senate careers. Backed by the Tea Party, Mourdock's victory is being seen by Democrats as an unexpected opportunity to win the Republican seat in the fall and cling to their slim majority in the Senate.Coats, who will become Indiana's senior Senator next year, urged GOP voters to unite behind Mourdock.From Coats' office: "I congratulate Richard Mourdock on winning the Indiana Republican Senate nomination, and I encourage Hoosiers to support him in November. Our country can no longer afford more of the same failed economic policies from this Democrat-led Senate and White House. It is important that Hoosiers come together in the months ahead to send Washington a clear message that we need a more limited, fiscally responsible government. I also want to extend my sincere gratitude and thanks to Senator Lugar for his years of honorable service to the people of Indiana and our country. Senator Lugar is well-respected by members of both parties, and I am fortunate to have had the opportunity to work with him in both my current and previous Senate terms. From supporting Hoosier farmers to preventing nuclear weapons from ending up in the hands of terrorists, Senator Lugar has had a distinguished career. I wish him all the best in his future endeavors."In his concession speech, Lugar said he hopes Mourdock prevails in the fall against Democratic Congressman Joe Donnelly. However, the elder statesman issued a follow-up comment criticizing his rival for lashing out at his bipartisan efforts."His embrace of an unrelenting partisan mindset is irreconcilable with my philosophy of governance. Unless he modifies his approach, he will achieve little as a legislator," says Lugar.UPDATE:President Obama has issued a statement praising Lugar and expressing appreciation for his distinguished three decades of public service. In the Senate, Lugar served as a mentor for the president during his brief tenure but their relationship became a liability for the soon-to-be former lawmaker.From the White House: As a friend and former colleague, I want to express my deep appreciation for Dick Lugar’s distinguished service in the United States Senate. While Dick and I didn’t always agree on everything, I found during my time in the Senate that he was often willing to reach across the aisle and get things done. My administration’s efforts to secure the world’s most dangerous weapons has been based on the work that Senator Lugar began, as well as the bipartisan cooperation we forged during my first overseas trip as Senator to Russia, Ukraine and Azerbaijan. Senator Lugar comes from a tradition of strong, bipartisan leadership on national security that helped us prevail in the Cold War and sustain American leadership ever since. He has served his constituents and his country well, and I wish him all the best in his future endeavors.