INDIANAPOLIS -- Republican Richard Lugar has shown through a lengthy Senate career that he can broker compromises on international and domestic issues, and avoid the acrimony that often brings Washington to a halt.
It's those qualities that may end up costing the former Rhodes Scholar and Indianapolis mayor the seat he first won in 1976.
Lugar, one of the longest-serving senators, is facing perhaps his toughest GOP challenger ever in tea party-backed state Treasurer Richard Mourdock, who hopes to end the incumbent's 36-year Capitol Hill career with a victory in Tuesday's primary.
Mourdock has spent months arguing that Lugar is not conservative enough for the right-leaning state, and he hopes to benefit from the split between the party's establishment and conservative wings. The challenger, aided by outside groups, also has tried to make the anti-incumbent argument, portraying Lugar as nothing more than a Washington insider.
"When Dick Lugar moved to Washington, he left behind his conservative Hoosier values," Mourdock said in a recent ad.
The attacks have taken a toll. Public polls show a close race, though internal surveys by several Republicans show Mourdock with a slight edge.
Lugar, 80, has "had his turn," said Judy Young of Brooklyn.
Lugar and his supporters have tried to turn his Washington career into an asset by arguing that his deep relationships in the capital make him best positioned to represent Indiana Republicans.
"I'm not for Dick Lugar for what he's done, but for what he can do," Gov. Mitch Daniels said in a recent campaign ad. "Our point of view gets heard and has a better chance to win out with Dick Lugar."
If Lugar loses, the seat probably will become a top target of national Democrats hoping to retain a narrow Senate majority. The Democratic Senatorial Campaign Committee said President Barack Obama's campaign and independent groups would be expected to rally behind U.S. Rep. Joe Donnelly.
That's less likely if Lugar, who's seen as a strong general election candidate because of his bipartisan record, prevails Tuesday.
Friends and foes alike say while Lugar had the backing of much of the state's establishment, including Daniels, he was slow to recognize the threat that Mourdock posed. They point to warning signs nationally from the 2010 primaries that severely divided the GOP. Tea party-supported candidates beat incumbents such as Sen. Bob Bennett, R-Utah, and establishment hopefuls in primaries in Colorado, Delaware and elsewhere.
Lugar has given critics fodder to assail him as out of touch with Indiana and Midwestern values.
He sold his Indianapolis home in 1977, and Democrats are now using that against him. Democrats and tea partyers mocked the fact that he lived in McLean, Va., near Washington, and raised the residency issue with Indiana authorities. Lugar briefly was ruled ineligible to vote in Indiana and later was forced to change his voter registration to his family farm in Indianapolis.
He also had to pay the Senate for more than $14,000 spent on hotel stays for weekend visits to Indiana.
One Mourdock supporter, 49-year-old Alan Horton of Mooresville, asked, "How does a man who doesn't live in this state vote for himself?" Many others have the same question.
Lugar hasn't done much to woo the tea party. In fact, he blamed the tea party for keeping the Senate in Democratic hands after the 2010 elections by nominating candidates who were too conservative to win general elections in a few critical states.
He also struggled to find a message that would appeal to the tea party-infused Indiana GOP.
Initially, he focused on Obama, blaming him for not supporting construction of a Canada-to-Texas oil pipeline. Later, he turned his sights on Mourdock, attacking him as "untrustworthy" in a series of negative ads. Lugar's campaign spent at least $2.5 million on advertising to answer Mourdock's charges and cut him down. Republicans say that effort backfired because the attacks undercut Lugar's reputation as a statesman.
"Personally he's just not mean, but his campaign has been so mean that once Mourdock became quasi-credible and people listened to him, the negatives began backfiring," said former U.S. Rep. Mark Souder, who is neutral in the race.
Lugar acknowledges hiccups but insists he's pleased with his campaign's effort.
"Obviously you can always think back over things that could have been done better," Lugar said. "You never have 100 percent."
Mourdock, a former geologist and two-term treasurer, spent more than $2 million to press his message. He got help from the anti-tax Club for Growth, which has spent about $1.7 million assailing Lugar.
He has been a fixture in GOP circles for some time but had struggled to win an election until his 2006 run for treasurer. That office catapulted him into the national spotlight when he challenged the Chrysler bankruptcy in a case that reached the U.S. Supreme Court, and endeared him to tea party activists looking for a change.
He may be rewarded Tuesday.
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