Donald Trump, the Republican presidential candidate who has proven to be a rabble-rouser within past weeks, is finally receiving inner-party reactions to his offensiveness and odious public comments.

After claiming Republican Senator John McCain was not a war hero, Trump has won the disapproval of yet another fellow presidential hopeful, Florida Sen. Marco Rubio, who said on Sunday he believes Trump is not fit to be president. 

Rubio believes that Trump's remark about the 2008 GOP presidential nominee was not only an insult to McCain, but also all prisoners of war.

"He's saying that somehow if you're captured in battle you're less worthy of honors," Rubio said on CNN's "State of the Union". "It's not just absurd, it's offensive. It's ridiculous. And I do think it's a disqualifier as commander in chief."

As the presidential race continues, Trump has begun to command attention with "offensive things that he is saying," said Rubio.

Trump made the controversial comments at a recent speech at a forum in Iowa, telling the attentive audience that McCain was not a war hero and was simply shot from the sky in Vietnam. He then mocked, "I like people who weren't captured" -- an apparent reference to McCain's six years spent in Vietnam as a prisoner of war.

Unapologetic and brash, Trump has said that he supports veterans and McCain failed them. Later, after an appearance on ABC's "This Week," he stated, "I will say what I want to say. I will do far more for veterans than John McCain has done for many, many years, with all talk no action. He's on television all the time, talking, talking. Nothing gets done."

McCain joined the United States Navy, graduated from the U.S. Naval Academy and became a naval aviator, flying a ground-attack aircraft from aircraft carriers. He was captured by the North Vietnamese in 1967, and was a POW until 1973, having endured years of torture. Trump, on the other hand, had a medical deferment from the draft in 1968, but has attempted to downplay that fact and has evaded recent questions on the subject, according to Politico.

McCain summoned Trump's ire last week by remarking that Trump "fired up the crazies" at a Phoenix rally when making comments about immigrants.

This is Donald Trump's second major self-created firestorm in his still-young campaign for the Republican ticket for the presidential race in 2016. Trump sparked controversy weeks ago when he stated that Mexican immigrants were drug dealers and "rapists".

His problematic words sparked widespread reactions from businesses, Hispanic leaders and celebrities -- although there was a notable lack of response from the GOP.

However, Trump's latest comments caught a reaction from the Republican establishment, and his GOP primary competitors went to social media and on TV to communicate their frustrations with "The Donald". Republican contender Rick Perry called Trump over the top and told NBC's "Meet the Press," that his comments were ''really offensive."

Following Trump's remark about McCain, the former Florida governor Jeb Bush tweeted, "Enough with the slanderous attacks." While Texas Sen. Ted Cruz and former Arkansas Gov. Mike Huckabee reportedly agree that McCain is a hero, they've failed to denounce Trump so far.