Rubio Says Des Moines Register Endorsement Doesn't Make Him Establishment Pick

— -- Sen. Marco Rubio downplayed the endorsement of the Des Moines Register Sunday, saying the backing of Iowa's most widely-read newspaper ahead of the caucuses doesn't make him the GOP establishment's pick for the Republican nomination.

"It means that if I win the nomination, I'm going to unite the party, and we're going to beat Hillary Clinton," Rubio said in an exclusive interview with ABC News ahead of his town hall in Cedar Rapids, Iowa.

Rubio "has the potential to chart a new direction" for Republicans, the paper's editorial board concluded in its endorsement, and "represents his party's best hope" to retake the White House in November.

Since 1996, the candidate endorsed by the Register has gone on to become the Republican Party's eventual presidential nominee.

The Florida Republican, who also said he was "grateful" for the Register's endorsement, has struggled to gain traction in Iowa ahead of the caucuses early next month, placing third in a Fox News poll of the state released Sunday behind Sen. Ted Cruz, R-Texas, and Donald Trump.

In recent days, several top Republicans appear to be coming to terms with a potential Trump victory in Iowa over Cruz. Iowa Gov. Terry Branstad said he wants Cruz defeated in his state. Former Kansas senator and 1996 GOP presidential nominee Bob Dole told the New York Times the Republican Party would suffer with Cruz as the nominee, compared to Trump.

Asked if Trump's standing hurts his chances, Rubio, who has received endorsements from more than a dozen members of Congress, said voters should resist supporting the "next person in line or who the people in Washington tell us we're supposed to be voting for."

Rubio, who will appear Monday with Sen. Joni Ernst, R-Iowa, said Ernst hasn't taught him how to "make 'em squeal" in Washington -- a campaign pledge from the freshman senator who grew up on a hog farm.

"You're not going to see ads like that from me," he laughed. "I didn't grow up around hogs."