Getting elected to Congress the first time is the hard part. After each subsequent reelection, the threshold for getting kicked out reaches higher and higher, as the incumbent becomes a fundraising machine with name recognition and a familial familiarity with his or her constituents. Mississippi Sen. Thad Cochran and Kansas Sen. Pat Roberts have proved this true in 2014, and Tennessee Sen. Lamar Alexander hopes to turn the trend into a hat trick today.

But it's hard to find someone who has tested the power of incumbency so doggedly than someone else running for reelection today in Tennessee — Republican Scott DesJarlais, a two-term representative in District 4.

The then-political novice DesJarlais first won election in 2010. Weeks before the 2012 election, papers from his 2001 divorce were released, and they showed that the former doctor had engaged in sexual relationships with patients, medical center co-workers and a drug company representative. The Chattanooga Times Free Press's account of the divorce papers noted, "Serving a dual role as doctor and lover, DesJarlais prescribed one patient pain medication and lavished her with an $875 watch and a plane ticket to Las Vegas, records show." The staunchly antiabortion rights representative also encouraged his ex-wife to get two abortions, and when one of the patients he was seeing said she was pregnant, he also advised that she get an abortion.

If that weren't enough, during the 2010 campaign, he faced allegations of violent behavior toward his ex-wife, such as dry-firing a gun outside the bedroom door while she was inside.

Nonetheless, he was reelected in 2012 by a comfortable margin, telling constituents that he had no plans to resign despite many calls for him to do so. He told the Knoxville News-Sentinel: "I am human. I don't think I ever put myself out there to be somebody that was perfect. I put myself out there as somebody who wanted to serve the public. I will serve as long as the people want me to serve."

Given all that baggage, he started the 2014 midterms at a tremendous disadvantage. In its list of the 10 most vulnerable members of Congress, Roll Call wrote: "If there was a No. 1 on this list, it would be DesJarlais. Bombshell revelations about his personal life are all but sure to sink him next year." In National Journal's list of the "Top 10 Lawmakers Who Could Lose a Primary Next Year," they wrote, "It's rare to see the name of Republican Scott DesJarlais without the adjective 'embattled' attached to it these days." 

His opponent, Tennessee state Sen. Jim Tracy, has outraised him, and several Tennessee politicians have abandoned DesJarlais to support his opponent. He seemed like a goner.

And yet, it appears that DesJarlais might actually win. DesJarlais's supporters started to pitch in last month — seeing that he still had a chance — and the incumbent, who announced that he is fighting cancer in July, managed to outraise Tracy. DesJarlais has even received donations from his fellow House incumbents — including Speaker John Boehner (R-Ohio) and Majority Leader Kevin McCarthy (R-Calif.).

A local observer of the race told Politico“Several weeks ago, the race seemed to be with the incumbent, odd as that may seem.”

If that doesn't prove the immense power of incumbency, we don't know what does.

Besides the perks of incumbency — voter recognition, support from colleagues — there are a few other things helping DesJarlais. First, there are seven candidates on the ballot in today's primary. Besides Tracy, there is John Anderson — a political activist, retired skydiver, kung-fu movie actor, ballroom dancer and person who "traveled to the mountains of western Mexico in 2012 to learn Yaqui medicine dance" — as well as Yomi Faparusi, Steve Lane, David Tate and Michael Warden. All of those competitors could dilute the anti-DesJarlais vote. As National Journal pointed out today, antiabortion rights groups have been silent in the race.

On top of that, DesJarlais's scandal reached its peak only days after his last successful reelection bid. Although DesJarlais didn't pick the timing of  the release of those divorce trial transcripts, they arrived at a weirdly optimal time for his future career prospects — after his 2012 primary and still 22 months before his 2014 primary (DeJarlais's district is safe in the general election). People have had time to forgive him, or at least forget his transgressions. One voter told the Tennessean: "Prior to this year, I'd never heard of it, to tell you the truth. Didn't have an impact on what the issues are."

For DesJarlais, the power of incumbency might be so strong that people are unable to even remember what he did wrong.

No one know for sure how the race will turn out — polling in Tennessee for this primary is nearly nonexistent — but it's safe to say that the fact that we're even talking about DesJarlais's having a shot is because he's an incumbent.