U.S. Sen. Pat Roberts didn't have to engage in deep thought about outcome of the initial 11 elections of his political career — eight 1st District congressional contests and three Senate showdowns.

He won them all with more than 60 percent of the vote.

The 2014 re-election campaign for Senate against independent Greg Orman, won by Roberts 53 percent to 42 percent, was an opportunity for the clear favorite to sweat a bit. The upcoming 2020 cycle, with Kansas victories by Democrats Laura Kelly and Sharice Davids in the rear-view mirror and President Donald Trump potentially on the ballot, presents a real choice for Roberts.

Will he, at age 82, ask Kansans to elect him for the 13th time? He's expected to soon reveal whether he's ready to reach for a baker's dozen. If he's in, Roberts might not draw a serious primary challenge. But there's a cluster of potential alternative candidates if he took a pass on another six-year term in Washington, D.C.

"Republicans have a deep bench in Kansas," said Patrick Miller, a political scientist at the University of Kansas. "This could include Kris Kobach, Jeff Colyer, Derek Schmidt, or even some of the newer faces like Scott Schwab or Jake LaTurner."

Kobach and Colyer leave public office in January, the result of campaign defeats. Both have spoken about the prospect of joining the Trump administration. In November, Schmidt was re-elected attorney general, Schwab was elected secretary of state and LaTurner won the race for state treasurer.

All four members of the Kansas congressional delegation -- the re-elected Roger Marshall and Ron Estes, and the departing Lynn Jenkins and Kevin Yoder -- could be in the conversation. Perhaps Marshall would have the edge because both Roberts and U.S. Sen. Jerry Moran, R-Kan., used the rural 1st District congressional seat as a launching pad for the 100-member Senate.

The list of Democratic Party prospects includes former U.S. attorney Barry Grissom, Gov.-elect Laura Kelly, former Gov. Kathleen Sebelius, U.S. Rep.-elect Davids and former state Rep. Paul Davis. Brent Welder, who lost the 3rd District primary to Davids, might take part. Here's a bitter reality: No Democrat has held a U.S. Senate seat in Kansas since 1939.

"We are still seriously considering the possibility of running in 2020," Grissom said in an interview Wednesday. "We're exploring how much money it's going to take. As someone who still has to work for a living, I don't take that lightly."

He said another consideration was placement of his family, friends and colleagues in the middle of a campaign process that looks more and more like a meat grinder.

Davis, the Democrat who narrowly lost the 2nd District congressional campaign in 2018 and the governor's race in 2014, appears to have taken himself out of contention by declaring his political career over. Orman, who ran a credible campaign for U.S. Senate against Roberts in 2014 but never gained good traction in the 2018 governor's race, likewise said he wouldn't seek office again.

Jenkins, who exits the U.S. House in January after five terms, set up a lobbying firm that could prove lucrative to the Republican. Yoder's loss to Davids last month, despite advantages of incumbency, suggested he might not be viable statewide. It was one loss, but depth of the GOP talent pool meant the party's voters didn't have to be as forgiving as Democrats.

Other outside-the-box possibilities include U.S. Secretary of State Mike Pompeo, who left his U.S. House district in Kansas to work for Trump at the Central Intelligence Agency and U.S. Department of State. Another could be Johnson County radiologist Milton Wolf, who undermined his Tea Party primary against Roberts in 2014 by joking about X-rays of injured and dead people that he posted to Facebook.

Miller cautioned against neglecting the appeal of unconventional candidates from business, the Legislature or municipal government.

"You never know who can actually build a good campaign and get momentum when a campaign actually starts," he said. "If Roberts retires, then it's entirely possible that our next senator is someone whose name we don't recognize right now."

He said an advantage for all candidates in Kansas was the relative low cost of conducting a statewide campaign. 

"A Senate seat in Kansas is still pretty cheap," Miller said. "So, unlike say Texas or California, you don't have to plan this years in advance to raise tens of millions of dollars."