Jenna Lee pressed Jeb Bush on why he went after Sen. Marco Rubio (R-Fla.) last night over his missed Senate votes. 

In one of the more memorable moments between the candidates at the 3rd GOP debate, Bush chided Rubio for not "showing up to work."

"What is this, a French work week?" he joked, suggesting that Rubio should resign from the Senate while he campaigns for president. 

But Rubio got the bigger response for his cool counter.

"Someone has convinced you that attacking me is gonna help you. ... My campaign is gonna be about the future of America. It's not gonna be about attacking anyone else on this stage," said Rubio.

Bush stood by the point on "Happening Now" today, adding that he was cut off before he could finish what he wanted to say.

Lee asked why Bush "felt compelled to demonize Rubio" in that manner.

Bush answered that he was not trying to "demonize," repeating that Rubio has the worst attendance record in the Senate. 

Lee then pointed out a little bit of the criticism Bush has been taking since last night for the attack on Rubio's voting record. 

Bush said he doesn't see it as a "mistake."

"It's a mistake to run for office and not serve. He can do both, but the simple fact is he's not doing that," said Bush. 

Bush then went after Rubio, Ted Cruz and Rand Paul for what he sees as a lack of accomplishments in the Senate. 

"You can count on two fingers the number of bills they've sponsored that have become law," said Bush, arguing he believes he can go to Washington and solve the "gridlock."

Watch the interview above.

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