The third Republican presidential debate Wednesday night turned ferocious early on, with candidates attacking one other.
"You should be showing up to work," Jeb Bush said to Marco Rubio. "The Senate – what is it, like a French work week? You get like the three days to show up? Just resign and let someone else take the job."
Bush was slamming Rubio for missing so many votes in the Senate while running for president.
"The only reason you're doing it now is because we're running for the same position and someone has convinced you that attacking me is going to help you," Rubio responded.
Ben Carson, rising in the polls recently, explained how his 15 percent flat tax would work.
"You also have to get rid of all the deductions and all the loopholes" he told the audience at the University of Colorado in Boulder. "You also have to do some strategic cutting."
But Ohio Gov. John Kasich said Carson's proposal is unrealistic.
"This stuff is fantasy – just like getting rid of Medicare and Medicaid. Come on... you don't scare senior citizens with that. It's just not responsible," Kasich said, chiding his conservative counterparts.
Then Donald Trump hit back at Kasich.
"He was nice," said the New York billionaire. "He was such a nice guy. Said he was never going to attack, but then his poll numbers tanked. That's why he's on the end and he got nasty. He got nasty!"
Ted Cruz touched on his own tax plan that he had unveiled hours earlier.
"It is a simple flat tax," explained the Texas junior senator. "For individuals, a family of four pays nothing on the first $36,000. After that, you pay 10 percent as a flat tax going up — the billionaire and the working man. No hedge fund manager pays less than his secretary."
Trump and Carson – both front runners – didn't attack each other.
Rubio got a lot of air time and had some strong moments.
The Florida senator was only second to Carly Fiorina with the amount of air time, logging nine minutes and 49 seconds, according to a tally by The New York Times. Trump, Kasich and New Jersey Gov. Chris Christie rounded out the top five with the most speaking time.
Carson was second-to-last, and Jeb Bush logged the least amount of time on camera, the Times reported, with six minutes and eight seconds.
One interesting note: Bush was no longer center stage next to Trump because he has slipped in the polls, and therefore moved off to the side.
Debates have drawn millions of viewers this year, and with less than 100 days before the first vote is cast in Iowa, it's up to voters to select who stood out.
Jason Whitely reported from Dallas