LAWRENCEBURG, Tenn. -- After losing his first bid for Tennessee governor 40 years ago, Republican Sen. Lamar Alexander shed his blue suit and buttoned-up appearance for a plaid shirt, hiking boots and a 1,000-mile walk around the state.
The goal was to connect with voters on a personal level, to make sure he could never be accused by any rival of not being one of them.
"I think Tennesseans and I know each other pretty well," Alexander said. "It's hard for me to come to Tennessee without meeting one or two families in whose home I spent the night when I walked across the state."
But after roughly four decades in office -- two terms as governor and two in the U.S. Senate, with two runs for president mixed between -- Alexander faces a challenge in the state's Thursday primary from a pair of Tea Party-styled primary challengers who have tried to cast the 74-year-old incumbent as out of touch with the state's increasingly conservative electorate.
"The voters are smart enough to see through the facade of what he's running on, which is a legacy that's over 30 years old as governor," said state Rep. Joe Carr, one of the two Republicans seeking to deny Alexander a third term. "People are going, 'OK, but what have you done in 12 years as United States senator?"'
Should Carr or Memphis radio station owner George Flinn prevail against Alexander on Thursday, they would be the first challenger to knock off an incumbent U.S. senator in this year's midterm elections. So far this year, the argument that sitting senators have lost their connection with voters hasn't been a winner.
In Kentucky, the ultimate Senate insider, Minority Leader Mitch McConnell, had no trouble holding back Tea Party challenger Matt Bevin. It took a runoff to do it, but Sen. Thad Cochran also beat back an effort from state lawmaker Chris McDaniel to "primary" him in Mississippi.
The latest win for a Senate incumbent, and failure for the "insider" argument, came Tuesday when Kansas GOP Sen. Pat Roberts outpaced radiologist Milton Wolf. Roberts survived despite telling a radio interviewer last month: "Every time I get an opponent -- uh, I mean, every time I get a chance -- I'm home."
Alexander sought to avoid any chance Carr or Flinn could make that case against him by locking down key endorsements early. He's spent the final few weeks of the campaign on a 35-stop bus tour around the state stressing his ability to get results in a divided Senate.
Fred Thompson, Alexander's predecessor in the Senate and fellow former staffer for the late Senate Majority Leader Howard Baker, R-Tenn., said Alexander's experience and deal-making capabilities will be all the more crucial if Republicans regain the majority in the Senate in November.
"We're going to need leadership like never before," he said. "We're going to need people who know how to get things done, who have demonstrated throughout their political careers strong conservative Tennessee values."
On Wednesday, Alexander's tour took him to Lawrenceburg, the hometown of Thompson, who was along for the ride and introduced the senator's speech at a restaurant on the town square. Alexander said afterward that he's worked to maintain close contacts made during his walking tour through several generations of families.
"I've stayed very connected to Tennessee and Tennesseans know that," Alexander said. "The question is do they want to give me the opportunity to continue to be the kind of senator that I was as governor, which is to try to get results."
Alexander has outspent Carr by a ratio of five-to-one through the most recent campaign finance disclosures, but Carr said voter unrest over issues like immigration should be enough to make up for his vast disadvantage in fundraising. Reminded that he once predicted it would take more than $5 million to oust the incumbent, Carr -- who has raised about $1 million -- laughed and said: "I was wrong."
Also on the Tennessee ballot Thursday is embattled Republican Rep. Scott DesJarlais, a physician from the small south Tennessee town of Jasper who won re-election in 2012 despite revelations that he once urged a patient he was dating to seek an abortion.
After the election, court officials released transcripts of divorce proceedings that included DesJarlais admitting under oath that he had eight affairs, encouraged a lover to get an abortion and used a gun to intimidate his first wife during an argument.
Last year, DesJarlais was reprimanded and fined by the Tennessee Board of Medical Examiners in May for having sex with patients. But the congressman has since doubled down on his Tea Party credentials and has dismissed the details about his personal life as "old news." He faces state Sen. Jim Tracy, who has far outraised the incumbent.
Other contested congressional primaries include the latest primary challenge to Democratic Rep. Steve Cohen, a white and Jewish Memphis native, in the state's majority black 9th Congressional District. Challenger Ricky Wilkins, an attorney and African American, has sought to highlight ethnic and racial differences between Cohen and his constituents in the district, which Cohen has represented since 2006.