The fact that he opted not to run in 2012, when the GOP field was extremely underwhelming and Thune wasn't up for reelection, suggests that he's more interested in pursuing his career in the senate, rather than the White House.
That may be true, but I also think he was worried about the Tea Partiers being upset at TARP and Obama's personal popularity, causing Thune to lose.
I just heard that he supported Term Limits, so it would make more sense for him to "not run for a 3rd term" if that was the case. Maybe he'll run for governor instead, or he's expecting to be VP. But if he ran in Iowa, he will likely win the caucus.
He talked about term limits when he first ran for his House seat in the 90s, saying that he would only serve three terms in the House (which he held himself to). But has he talked about it at all since being elected to the Senate? Term limits were a much bigger issue in the 90s, but hardly anyone cares about them now.
It's possible that he agreed to limit himself to three terms in the House because he thought it would help him win, and because he figured he'd be running for a Senate seat eventually anyway, and 6 years in the SD's lone House seat would be enough to build his name recognition. But is there any evidence that he still cares about term limits now? He could well intend to be a Senate lifer.
Taking a stand on Term Limits can be a very personal thing. You are essentially saying that long-term power will corrupt the politician because he/she will get too comfortable in the seat and won't be held accountable. Of course, when a person gets into power in the Senate, and realizes longevity is essential, and also gets comfortable with the role and the authority, then the idea of "term limits" may slide. Maintaining support for Term limits may come down to personal integrity. Now, Thune may have supported "term limits" for purely political reasons without actually believing in them, and that would be a scummy thing to do. But he may also be ambitious to continue his climb to new political offices. I think he tried to run for governor before the senate. So he has to decide where his window for the "presidency" opens, if he wants to become president one day. He's still relatively young, so he can run for a 3rd Senate term. But voters like youthful presidents, so after a person gets over the age of 60, they become less exciting.
As for the Senate term limits, some people like Brownback maintain their word and integrity on 2 terms. Others like KBH will run for a 3rd term anyways.
Power corrupts... a dishonest person. Power can also be a means of service. Membership in the House or Senate is lucrative enough that even someone who lives on the pay alone is still rich. Joe Biden was #100 in the US Senate in personal wealth in 2008, and he was still a rich man.
Outright bribery is rare among our elected officials. There might be sleazy dealings between lobbyists and re-election campaigns, and until recently some were dealing on insider information on legislation -- which was criminal in almost any other context. It is now outlawed.
Of course it takes time for any politician to go corrupt if he isn't to begin with. Many choose not to go corrupt.
John Thune is best known for defeating the Senate Majority Leader of the time. Since then he has done little except to follow the party line in his voting. To be sure it is probably wisest to avoid national media. If he were one of the leading lights of the GOP he would be big news by now. National news media were excited about some Illinois State Senator who had about every usual hallmark of an up-and-coming political leader except one as he ran for a US Senate seat. Talk of John Thune as a significant candidate for President in 2016 is based on things that he has yet to do, including getting recognition outside of South Dakota.
