Marco Rubio snags South Carolina Sen. Tim Scott's endorsement after Iowa caucus

Sen. Marco Rubio scored a key endorsement on Tuesday as South Carolina Sen. Tim Scott gave the Republican presidential hopeful his backing.

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In a video posted to Rubio's YouTube page, Scott said the Republican party has "one shot" to beat Hillary Clinton in 2016 and "that shot is Marco Rubio."

"I'm putting my confidence and trust in Marco Rubio because I believe he takes us to that better future," Scott said.

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The endorsement -- long expected -- came after Rubio had a surprisingly strong showing in Monday's Iowa caucus, coming in a close third place with 23 percent behind Ted Cruz and Donald Trump.

Rumors that Scott would back Rubio have swirled for some time, with the senator having appeared on the campaign trail with Rubio several times. Rep. Trey Gowdy -- another South Carolinian who himself endorsed Rubio -- last week said Scott would campaign for Rubio in the state, further hinting at an impending announcement.

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Now that it's official, the endorsement is expected to give Rubio a boost in the crucial state of South Carolina -- where the candidate may be looking to bag his first primary win.

Scott is one of South Carolina's most popular politicians -- enjoying support from conservatives and moderates alike -- and his endorsement coupled with Gowdy's gives Rubio the backing of two of the most well-respected lawmakers in the state.

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Many of Rubio's top strategists -- including his campaign manager and top super PAC adviser -- also have deep roots in South Carolina, potentially giving Rubio an added advantage in the primary.

But first, Rubio has to make it through New Hampshire -- though his chances in that state's primary also look favorable on the heels of Monday's stronger-than-expected showing in Iowa.

RCP Poll Average for Rubio vs. Clinton - 2016 General Election InsideGov

Rubio finished third, but performed far better than most polls have shown, coming in just one point behind Donald Trump and just five points behind winner Ted Cruz in the final tally.

The finish has handed Rubio a burst of momentum heading into the weeklong-sprint toward the New Hampshire nomination.

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