Orman, 45, is a political enigma. Over the years, he's donated money to both liberal Sen. Al Franken (D-Minn.) and the National Republican Congressional Committee. He says he voted for President Obama in 2008 and Mitt Romney in 2012. And he won't reveal which side he would choose in the Senate.
But national Democrats have been mum about Taylor's sudden departure, fueling speculation the party believes there is a very good chance Orman would side with them. Running in a deeply conservative state, Orman is carefully avoiding any move that would link him too closely with Democrats. At the same time, he's casting himself as a much more moderate alternative to Roberts, who he says has adopted "Ted Cruz's voting patterns."
In a telephone interview with The Washington Post last week, Orman decried the partisan gridlock that has seized Congress. He said that he would likely side with whichever party is in the majority and talk to both sides if he ends up the deciding vote. With a competitive battle for the majority underway, that's a possibility.
"I hold both sides equally accountable," he said.
Orman presented himself as a moderate in the mold of Bob Dole, the former Senate majority leader from Kansas. He took aim at Roberts for voting against the farm bill, and lambasted him for not voting on the VA reform bill.
On immigration, he emphasized the importance of securing the border -- but also said supports a path to citizenship for undocumented immigrants and that he would have supported the comprehensive reform bill that passed the Senate last year.
"I think if you're undocumented and you are here, you should have to register with [U.S. Immigration and Customs Enforcement], you should have to pay a small fine or perform community service as an acknowledgement that you've broken the law," he explained. "Then you should have to hold down a job, pay taxes, obey our laws. And if you do all those things, I think you should be able to continue to live here and work here."
Orman was one of five children of a nurse and a furniture store owner in Stanley, Kan. He graduated from Princeton University, where he was a member of the College Republicans, in 1991 with an degree in economics. Not long after, he founded a company that installed energy efficient lighting systems. In 2004, he co-founded Denali Partners, LLC, an investment firm.
Disillusioned by the George W. Bush administration, according to lengthy explanation of his political history posted on his campaign Web site, Orman decided to become a Democrat. His first foray into elected office was in 2007, when he briefly explored a run against Roberts as a Democrat before pulling the plug on that idea.
He's parked himself firmly in the middle in the years since that short-lived bid. Orman founded the centrist the Common Sense Coalition in 2010. He told The Post -- after initially balking -- that he voted for Obama in 2008 and Romney in 2012. Obama's "very, very partisan approach to health-care," Orman said, led him to opposing a second term.
Campaign finance records reveal that Orman has given to both Democrats and Republicans over the years. About two years after giving money to Obama, have wrote a check to a political action committee founded by Republican Scott Brown.
Orman, for his part, is not taking money from political action committees in his campaign. Through mid-July he had more than $362,000 in his campaign account -- a fairly impressive sum for an inexpensive state like Kansas. And he's left the door open to dipping into his own pockets for more.
Roberts, who is still recovering from a bruising primary campaign in which he was sharply criticized for staying with supporters when he is in Kansas instead of his own home, has signaled that he will try to portray Orman as far too liberal for Kansas.
"We are confident that Kansas voters will quickly see through this charade foisted on Kansas by Orman and his Democrat allies," said Leroy Towns, Roberts's campaign manager, in a statement.
Amid his political shifts over the years, did Orman ever vote for Roberts in a primary or general election?
"Not that I recall," he said. "But I don't remember everybody I voted for over the last 25 years."