ANALYSIS: How Marco Rubio Grabbed the Spotlight and 6 Other Republican Debate Takeaways

— -- The third Republican debate may have been the most consequential so far.

With almost half of the candidates on stage at the tipping point between being a top contender or fading back into the pack, the stakes were high. One-time favorite Jeb Bush was in need of a spark. And Marco Rubio was quickly becoming an establishment alternative to Bush. Not to mention -– Ben Carson is on the cusp of overtaking Donald Trump for the front of the GOP pack.

Still, all the buzz was about the second-tier race: Bush and Rubio dominated post-debate coverage, making it hard to remember that Trump and Carson garner almost triple their support in almost every recent national poll.

Here are the seven main takeaways from Wednesday night’s third presidential debate:

1. Marco Rubio isn’t flying under the radar anymore. He came out of Wednesday’s night debate with rave reviews. There’s no doubt he had a strong performance and his showdown with his former mentor, Jeb Bush, struck a brutal blow to the one-time frontrunner’s already shaky candidacy. Today, the Rubio campaign may be flying high and even raking in some post-debate donations, but there is a downside to being on top. Now there’s no way Rubio can fly under the radar anymore. With polls showing Rubio rising and last night’s performance behind him, he will face more scrutiny and be a target of rivals. A campaign on the rise often brings new difficulties, but that’s only something eventual winners have to go through.

2. Jeb Bush is in serious trouble. There’s no way to sugarcoat last night for Bush’s campaign, not to mention his supporters. He not only didn’t have a break out moment, but his face off with his one-time protégé Marco Rubio was a stand-out moment for his rival. The Bush camp telegraphed they were going after Rubio’s voting record, making absolutely sure everyone, including the Rubio camp, were ready when that hit came. The problem: Bush had no comeback. Of course, one bad debate doesn’t kill a candidacy, but the former Florida governor has been struggling in the polls and now it’s time to keep donors from going into full-on panic mode. There’s another debate around the corner—Nov. 10 — and everything could be riding on that trip to the podium.

3. No harm, no foul for Ben Carson and Donald Trump. The two frontrunners in this race are Trump and Carson –- at least that’s what the polling said. But they definitely weren’t the main attractions last night. Trump even went 28 minutes at one point without speaking. They didn’t flop, but no one is raving --or even talking about --their largely-absent performances. They made no errors, but there were no break out performances either. It’s status quo for the two contenders at the top of the polls. Will it matter to voters? We will be watching the next slate of polls very closely.