President Barack Obama is having a hard time not taking sides as Hillary Clinton and Bernie Sanders battle for the Democrats' presidential nomination and, potentially, a chance to succeed Obama in the Oval Office.

Obama revealed his "obvious affection" for Clinton, his former secretary of state, in a 40-minute interview with Politico, the Washington publication reported. His preference may have to do with Clinton's experience and Obama's assessment that she is best prepared to tackle the unique demands of the presidency, Politico speculated.

"(The) one thing everybody understands is that this job right here, you don't have the luxury of just focusing on one thing" as president of the United States, Obama mused.

While he refused to name a personal favorite, the president was prepared to analyze the Democratic race and point to the strengths and weaknesses of both Clinton and her main challenger.

'Luxury of being a long shot'

"Bernie came in with the luxury of being a complete long shot and just letting loose," Obama noted about the Vermont senator. "I think Hillary came in with the both privilege -- and burden -- of being perceived as the front-runner. You're always looking at the bright, shiny object that people haven't seen before -- that's a disadvantage to her," he explained.

In the critical early-caucus race in Iowa, Clinton and Sanders are virtually tied in the polls as of now, CBS News reported. But Sanders will eventually have to prove that he does not only have an appealing message but is also prepared to lead the free world, the president suggested, according to Politico.

Presidency comes with 'dramatic' moments

"I don't want to play political consultant, because obviously what he's doing is working. I will say that the longer you go in the process, the more you're going to have to pass a series of hurdles that the voters are going to put in front of you," he said.

"I was sitting at my desk there just a little over a week ago ... writing my State of the Union speech, and somebody walks in and says, 'A couple of our sailors wandered into Iranian waters. That's maybe a dramatic example, but not an unusual example of the job," Obama concluded.