US President Barack Obama has publicly made fun of candidates the Republican Party is fielding for the presidential race in 2016, commenting that some of them say stuff "that makes no sense."

In a speech at the University of Wisconsin at LaCrosse, Obama mocked the Republican Party for having several presidential aspirants.

"You know, we've got some healthy competition in the Democratic Party, but I've lost count on how many Republicans are running for this job," Obama said in his speech.

"They'll have enough for an actual Hunger Games," he quipped, referring to the popular book and movie franchise where 24 individuals kill each other to win.

Obama also compared some Republican presidential candidates to "your crazy Uncle Harry" at Thanksgiving who says stuff "that makes no sense."

"That is an interesting bunch," Obama remarked, drawing laughter from his audience.

Fourteen candidates are currently vying for the GOP presidential nomination, including controversial tycoon Donald Trump and former Florida Gov. Jeb Bush, perceived to be the current frontrunner.

Two more Republican candidates, Wisconsin Gov. Scott Walker and Ohio Gov. John Kasich are expected to join the presidential race later this month.

In the same speech, the US President also criticised "mean" Republicans, who have often attacked Obama's economic performance, for proposing tax cuts and loosened regulations.

Obama said these economic proposals will hurt middle-class Americans and will benefit only the already wealthy ones.

"They're good people. It's just their ideas are bad," the President said of Republicans.

He also said he expects the Republican Party to come up with false statements to discredit his administration as the 2016 elections draw near.

"They're going to be making a whole bunch of stuff up, and when I say a lot of stuff, I mean a lot of stuff," Obama said in his speech.