Vicky Hartzler rode a Republican wave in 2010 to stun long-time Democrat Ike Skelton to represent much of central Missouri.
Hartzler held off facing stiff competition Tuesday from Cass County Prosecutor Teresa Hensley to win re-election.
With all 413 precincts reporting, Hartzler had 192,166 votes for 60 percent to Hensley's 113,044 votes for 35 percent.
Both women thanked their tireless supporters. Hensley said she was proud of the campaign she ran and harkened to lines from a famous Lee Ann Womack song.
"I want to thank you for the dance that you gave me this year. And I hope at some point you will join me again on the dance floor. We still have work to do.
Hartzler said she will focus the next two years on improving America's economy and "Obamacare."
"We've got to get this economy going again and we can do it by removing the onerous regulations and lowering our corporate tax rate to make us more competitive and we need to repeal Obamacare and replace it with some common sense health care reform," she said. "So there's some things we can do from a very practical level."
Hartzler derided President Barack Obama's health care reform while saying elected leaders in Washington must come together.
"We've got to work for the American people. That's what this is all about, serving them and moving our country forward. We've got to find that common ground and I believe we can. He says he wants to undue a lot of the onerous regulations. Let's get to talking about the specifics. We can lower our corporate tax rates so we're not the highest in the world."
The 4th Congressional District is a battleground that stretches from the Kansas border to parts of Audrain County.
The Fourth District includes substantial new turf added after Missouri lost one of its nine seats in the U.S. House after population declines. The new terrain includes Boone, Cooper, Howard and Randolph counties and parts of Audrain and Cass counties.
The population center of the district shifted from conservative Jefferson City to progressive Columbia.
Because of this and Hartzler's freshman status, she was considered one of the most vulnerable incumbents in the U.S. House.
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