Washington (CNN) Sen. Marco Rubio leads all Republican presidential hopefuls in a new poll released Thursday morning, capturing some momentum in the weeks after he became the third major Republican to announce his presidential campaign.

The Florida senator garnered support from 15% of the registered Republicans polled by Quinnipiac University, giving him a slight edge over his mentor Jeb Bush, the former Florida governor who won 13% of the vote in the poll.

Rubio also performed the best of all the potential Republican candidates in hypothetical head-to-head matchups against likely Democratic nominee Hillary Clinton, trailing her by only two percentage points.

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The poll -- surveying national Republicans and coming nine months before the first votes will be cast in the Iowa caucuses -- serves as a signal that Rubio has the potential to make a run at the nomination.