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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