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Republicans face off for third time on Wednesday

Rubio on the attack, Trump's got Carson in crosshairs

Washington CNN  — 

If the weekend news shows were any indication, the next Republican debate in a few days is going to be a doozy.

In a flurry of appearances on Sunday political talk shows, Donald Trump let it be known that he’s ready to take off the gloves and hammer Ben Carson. Florida Sen. Marco Rubio was increasingly willing to hit fellow Republicans. And, on the Democratic side, Vermont Sen. Bernie Sanders indicated he’s not going to let Hillary Clinton set her campaign in cruise control, even after two strong weeks.

2016 election candidates

Here’s a look at three themes that will reverberate through this week:

Trump attacks Carson

According to Trump, Carson is “very weak on immigration,” “cannot do with trade like I do” on the Trans-Pacific Partnership, and has “super low energy” levels – lower, in fact, than Jeb Bush.

The attacks – many coming in an interview with CNN’s Jake Tapper on “State of the Union” – signal that Trump has been stung by new polls that show Carson has seized the front-runner’s mantle in the first state to cast votes in the presidential nominating contest.

Trump like to call himself a “counter-puncher,” but he’s attacked Carson even while the retired neurosurgeon has largely stayed away from initiating clashes of his own.

Trump blasts Carson, says he lacks energy to be president

The aggressive approach suggests Trump is ready to draw the typically more reserved Carson out of his shell when Republicans meet Wednesday in Colorado for the their third debate, this one hosted by CNBC.

“He can’t do with a lot of things like I do, so we’ll just have to see what happens,” Trump said of Carson.

Carson, meanwhile, told NBC’s Chuck Todd on “Meet the Press” that he has dropped his angry teenage past, one in which he was violent.

“I do have a tendency to be relaxed,” he said. “I wasn’t always like that. There was a time when I was, you know, very volatile. But, you know, I changed.”

Carson’s violent past: Bricks, bats, hammers

Trump and Carson are also exchanging shots over religion after Trump told a crowd in Florida of Carson’s faith: “I mean, Seventh-day Adventist, I don’t know about. I just don’t know about.”

Carson questions authenticity of Trump’s faith

A feistier Rubio

As he settles in the top tier of Republican presidential candidates, Rubio, the Florida senator, is increasingly willing to slam his primary rivals.

He hit Trump on CNN’s “State of the Union,” saying the real estate mogul is unfit to become commander-in-chief due to his limited foreign policy expertise.

Santorum: Trump’s remarks show he still learning foreign policy

“To this point in the campaign, he has not proven an understanding of these issues or the preparation necessary to be the commander-in-chief of the most powerful military force in the world,” Rubio said.

Among the biggest questions of the GOP nominating process thus far has been whether Rubio can eventually overtake Bush as the favorite of moderate and moneyed “establishment” members of the party eager for an alternative to political newcomers and outsiders like Trump, Carson and Carly Fiorina.

Rubio has also begun taking aim at Clinton, the Democrat who he says is certain to be that party’s nominee.

Look for Rubio to come on strong in the debate this week.

Clinton wears a bigger target

It was a big two-week string of victories for Clinton: A funny and well-received appearance on “Saturday Night Live,” a widely praised showing in the first Democratic presidential debate, a decision by Vice President Joe Biden to stay out of the 2016 race, and an escape from an 11-hour hearing on Benghazi without being hit by any new bombshells.

5 ways Joe Biden’s decision changes the 2016 race

But with the more solid ground she finds her campaign on now comes a bigger target she’ll wear.

With Biden staying out of the race and Jim Webb and Lincoln Chafee dropping their longshot campaigns, Clinton now faces a much Sanders says he is not ‘shouting’ at Hillary Clinton

Sanders showed new willingness to go after Clinton on Sunday, saying on CNN’s “State of the Union” that both Bill and Hillary Clinton supported a measure – the 1996 Defense of Marriage Act, which defined marriage as between one man and one woman – that was “homophobic.” It was the latest in his efforts to cast Clinton as a late comer to liberal causes he has supported for decades.

He said the law, since struck down by the Supreme Court, was pushed by GOP lawmakers – and “many of them, I’m sorry to say, were homophobic.”

“I think everybody at the time knew that it was simply homophobic legislation,” Sanders said.

“That legislation was anti-gay legislation. It was playing off the fears of a lot of Americans,” he added. “Now the good news – as Hillary Clinton just indicated – the culture has changed radically. … We have come a long, long way since that vote in 1996.”