Trump tells migrants to \'turn back now\' at Mississippi rally

(ROUGH CUT - NO REPORTER NARRATION) President Donald Trump and Vice President Mike Pence launched a rescue mission in Mississippi for a Republican candidate on the eve of a run-off election for the U.S. Senate, with Democrats hoping to win a seat in the state for the first time since 1982.

Trump appeared at two large, boisterous rallies in Biloxi and Tupelo, Mississippi, for Senator Cindy Hyde-Smith, who is in a close race against black Democrat Mike Espy in the deep South state.

The result of Tuesday's run-off will determine whether Republicans widen their control of the U.S. Senate to 53 to 47 seats when the new Congress takes office early next year.

Hyde-Smith remains a narrow favorite to win.

Trump also addressed the migrant caravan headed to the U.S. border with Mexico.

"It's very simple," he said.

"Turn back now, go back home.

We will not let you in.

We are not going to let you in.

Turn back now."