Romney Attacks Trump

WITH THE HELP OF AN ACCOMPLICE IN A CAR WAITING OUTSIDE HER HOME.

NOW TO CAMPAIGN 2016.

DONALD TRUMP HAS SOME PRIME REAL ESTATE.

IT'S THE COVER OF "TIME" MAGAZINE.

WELL, IN THIS CASE, IT IS NO HONOR.

THE MAGAZINE HAS CHECKED BOXES NEXT TO THE WORDS, BULLY, SHOWMAN, PARTY CRASHER AND DEMAGOGUE.

ONLY ONE BOX IS LEFT UNCHECKED.

THAT ONE SAYS, PRESIDENT.

TRUMP WAS THE TARGET OF A BLISTERING ATTACK TODAY FROM MITT ROMNEY AND AS YOU WOULD EXPECT, TRUMP FIRED RIGHT BACK.

CBS 2'S JESSICA SCHNEIDER LIVE IN THE NEWSROOM WITH MORE ON THE REPUBLICAN RUMBLE.

JESSICA.

Reporter: YEAH, MAURICE.

THE REPUBLICAN RACE REACHING A NEW LEVEL TODAY.

MITT ROMNEY MADE IT CLEAR HE DIDN'T SPEAK OUT TO ENDORSE A PARTICULAR CANDIDATE OR TO ANNOUNCE A RUN HIMSELF.

INSTEAD, HIS ONLY MESSAGE WAS DON'T VOTE FOR TRUMP.

DONALD TRUMP IS A PHONY A FRAUD.

HIS PROMISES ARE AS WORTHLESS AS THE DEGREE FROM TRUMP UNIVERSITY.

WHOO! [ APPLAUSE AND CHEERS ] Reporter: MITT ROMNEY NOT MINCES WORDS WHEN IT COMES TO THE CANDIDACY OF DONALD TRUMP.

BUT YOU SAY, WAIT, WAIT, WAIT.

ISN'T HE A HUGE BUSINESS SUCCESS? DOESN'T HE KNOW WHAT HE IS TALKING ABOUT? NO, HE ISN'T.

AND NO, HE DOESN'T.

Reporter: THE 2012 REPUBLICAN PRESIDENTIAL NOMINEE EMERGING FROM THE GOP ESTABLISHMENT TO TRY TO TAKE DOWN TRUMP.

TRUMP HAS WON NINE STATES SO FAR AMASSING 324 DELEGATES TO CRUZ'S 230 AND RUBIO'S 111.

THE BRASH BILLIONAIRE REBUTTED THIS AFTERNOON DISMISSING ROMNEY AND HIS WARNINGS TO VOTERS.

MITT IS A FAILED CANDIDATE.

HE FAILED.

YEAH! [ APPLAUSE AND CHEERS ] HE FAILED HORRIBLY.

HE IS A CHOKE ARTIST.

Reporter: TRUMP REPEATEDLY RAILED AGAINST ROMNEY FOR HIS FAILED BIT AGAINST OBAMA LAST ELECTION AND REMINDED REPUBLICANS THAT ROMNEY SOUGHT TRUMP'S ENDORSEMENT FOUR YEARS AGO.

I BACKED MITT ROMNEY.

BOO! I BACKED HIM.

YOU CAN SEE HOW LOYAL HE IS.

HE WAS BEGGING FOR MY ENDORSEMENT.

I COULD HAVE SAID, MITT, DROP TO YOUR NOISE.

HE WOULD HAVE.

Reporter: ROMNEY RESPONDING SECONDS AFTER.

IF TRUMP HAD SAID FOUR YEARS AGO THE THINGS HE SAYS TODAY ABOUT THE KKK, MUSLIMS, MEXICANS, DISABLED, I WOULD NOT HAVE ACCEPTED HIS ENDORSEMENT.

THE STAGE IS NOW SET FOR ANOTHER WILD DEBATE TONIGHT.

RUBIO IS EXPECTED TO STEP UP ATTACKS ON TRUMP, THE FLORIDA SENATOR HAS ONLY WON ONE STATE BUT HE STILL IS FIGHTING TO BECOME THE ALTERNATE TO THE FRONT-RUNNER.

BEFORE WE CHOOSE DONALD TRUMP AS OUR NOMINEE WE'LL LOSE IN NOVEMBER.

Reporter: THE FIELD IS DOWN TO FOUR.

BEN CARSON WITHDREW ANNOUNCING LAST NIGHT HE SEES NO PATH FORWARD TO THE NOMINATION.

TED CRUZ MAKING A PLAY NOW FOR MORE SUPPORTERS.

IF YOU HAVE BEEN SUPPORTING BEN CARSON OR JOHN KASICH OR MARCO RUBIO, ALL GOOD HONORABLE MEN, WE WELCOME YOU ON OR TEAM.

Reporter: AND WITH THE REPUBLICAN FIELD NOW STARTING TO NARROW, THE QUESTION IS, WHAT HAPPENS TO THE DELEGATES OF CANDIDATES WHO DROP OUT? THE ANSWER IS TRICKY.

THE RULES VARY BY PARTY AND BY STATE WITH THE GOP SOME DELEGATES WILL STILL VOTE FOR THEIR ORIGINAL CANDIDATES IN OTHER STATES, THOUGH, DELEGATES MAY IMMEDIATELY.