Kasten, 79, won the Republican nomination to replace Nathan Cooper in the Feb. 5 special election. Cooper, a Republican, resigned his seat Aug. 14 in the wake of pleading guilty to two federal felony counts.
"I can do whatever it takes," Kasten said after the votes were counted. "And I've got a lot of offers to help."
Kasten will face Democratic nominee Mike Keefe, the former Cape Girardeau postmaster, and Libertarian George Webster, who works in health-care information technology, in the election.
Independent candidates wishing to enter the race have until Nov. 15 to submit petitions with 239 signatures from registered voters of the district in order to be on the ballot.
The 158th District Republican Legislative Committee met at Dexter Bar-B-Que to select the nominee, with 17 of the 18 members present.
Kasten stepped forward as a candidate this week, following the withdrawal of former Air Force Lt. Col. Wayne Wallingford and former J.C. Penney manager Harry Rediger. A third, mortgage and real estate broker Gary Lange, withdrew when Kasten announced her intention to run.
A fourth rival, Navy Lt. Cmdr. Clinton Tracy, who is on his way home from a deployment in Iraq, was represented at the meeting by his wife, Carrie Tracy, and his mother, Cape Girardeau Councilwoman Debra Tracy.
The committee's split on the nomination vote between Kasten and Tracy was not announced.
Committee member Morley Swingle, the Cape Girardeau County prosecutor, said he's pleased with the choice.
"Mary Kasten is the antidote to blind ambition," Swingle said. "She is the perfect candidate."
Kasten first won election to the Missouri House in 1982. She held the seat for 18 years, declining to run for re-election in 2000 when her late husband, Dr. Melvin Kasten, became severely ill.
Kasten was close politically to Cooper, serving as his campaign treasurer during his first race for office in 2004.
Under Missouri's term limits, Kasten is eligible to serve the remainder of Cooper's term and, if she chooses, seek one more term in the Missouri House. The term limits provision of the state constitution was passed in 1992 and took effect for candidates elected in 1994.
Before the vote, Carrie Tracy made a pitch for her husband. Clinton Tracy is in the Naval Reserve and was called to active duty. He is general manager of the family's Timberline International Forest Products. He is a graduate of the U.S. Naval Academy.
"He has a heart for the people of this community," Carrie Tracy said. "That is why we chose to come back after Clinton was in active duty in the military."
Kasten promised to follow the path she took previously in office, working to make Missouri a good place to do business, strengthen the education system, transportation and to make public assistance programs encourage work over welfare.
"We all have a really hard job to get out there and win because we know the other side is determined to take this seat," Kasten said.
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