(CNN) Sen. Marco Rubio is defending his stance against a ban on semiautomatic rifles -- claiming that the position is "well outside" mainstream opinion -- after he signaled an openness to limited gun control measures at a CNN town hall on school shootings.

"Banning all semi-auto weapons may have been popular with the audience at #CNNTownHall, but it is a position well outside the mainstream," the Florida Republican tweeted early Thursday morning.

Banning all semi-auto weapons may have been popular with the audience at #CNNTownHall, but it is a position well outside the mainstream https://t.co/18rMDwEfGs — Marco Rubio (@marcorubio) February 22, 2018

He added, "Wonder if media will ask politicians demanding #GunControl if they support popular sentiment at #CNNTownHall for ban of all semi-auto rifle?"

Wonder if media will ask politicians demanding #GunControl if they support popular sentiment at #CNNTownHall for ban of all semi-auto rifle? https://t.co/FAPoBFwE6I — Marco Rubio (@marcorubio) February 22, 2018

Polls, however, show widespread support for bans on certain guns. Although the AR-15 -- the weapon used in the Florida shooting -- is not technically defined as an assault weapon, a poll conducted by Quinnipiac in the wake of the massacre found that 67% support a nationwide ban on assault weapon sales.

And a poll conducted by Pew in June 2017 found that 68% support banning assault-style weapons.

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