Shoot first, answer questions later!

Democratic presidential front-runner Bernie Sanders withstood a barrage of attacks — some withering — Tuesday night from his six rivals, who mounted a last, best effort to slow his momentum heading into the South Carolina primary, said Democratic consultant Monica Klein, who rated the candidates’ performances for The Post.

The rest of the race remains in flux thanks to former New York City Mayor Michael Bloomberg’s late entry into the contest and his big spending, which has finally given Massachusetts Sen. Elizabeth Warren the foil she needed to define her campaign to voters, Klein added.

“Bernie was the one to beat on the stage and no one landed a real lasting punch as we head into South Carolina,” said Klein about the chaotic forum in Charleston. “Without Bloomberg on the stage, Bernie would have received the brunt of everyone’s attacks.”

She added: “Instead, they had a second target to shoot at, which helped insulate Bernie.”

Here’s how she ranked the performances.

Michael Bloomberg: The former mayor proved a half-billion dollars can’t buy you a personality. He performed slightly better than in his disastrous last debate, but it wasn’t enough as he got hammered again on stop-and-frisk and his comments about women.

Arrow: Down

Pete Buttigieg: He rankled Sanders on Cuba, and delivered another competent performance that provided no details about how he’d actually run the country. He won’t lose supporters, but he didn’t dominate the stage either.

Arrow: Sideways

Elizabeth Warren: She kept attacking Bloomberg — and kept scoring. Plus, she wisely differentiated herself from Sanders without attacking their shared progressive platform.

Arrow: Up

Bernie Sanders: He stayed on the offensive against Bloomberg’s immense wealth and withstood an onslaught of attacks from all sides — refusing to give his opponents the knockout punch they needed to slow his momentum.

Arrow: Up

Joe Biden: His slightly improved performance won’t deliver the momentum his campaign desperately needs. And his meandering delivery did little to comfort Democratic voters about how he’d fare on stage with President Trump.

Arrow: Down

Amy Klobuchar: A talented debater, Klobuchar delivered again — including a strong moment on the coronavirus as she urged voters to check the CDC website rather than visit her own campaign site.

Arrow: Up

Tom Steyer: The most interesting thing about his performance was his flannel tie. He needs to stop wasting space on the debate stage and invest his cash in down-ballot Democrats who could actually win.

Arrow: Down

Klein is a progressive political strategist and founding partner at Seneca Strategies, where she has worked with clients including state Sens. Jessica Ramos and Julia Salazar, Queens district attorney candidate Tiffany Cabán, and the Working Families Party. Prior to founding Seneca Strategies, Klein spent three years as a deputy press secretary to Mayor Bill de Blasio.