Marco Rubio & Jeb Bush
Former Republican presidential nominee Mitt Romney walks to his campaign plane with U.S. Senator Marco Rubio (R-FL) (2nd L), U.S. Representative Connie Mack (R-FL) (2nd R) and former Florida Governor Jeb Bush (R) REUTERS/Brian Snyder

Former Florida Governor Jeb Bush may not be officially running in the 2016 election but a new poll by NBC News and the Wall Street Journal revealed he edges out all other Republican contenders.

Bush is followed closely behind by fellow Floridian, Senator Marco Rubio, the poll suggests.

According to NBC News, 23% of GOP primary voters chose Bush as their first choice to win the party's primary. Rubio came in second with 18% of voters choosing him as their first choice. Another 14% chose Bush as their second choice, while Rubio earned 23% of votes as a second choice.

Rubio also earned great numbers when primary voters were asked which potential candidate they could definitely see themselves supporting, NBC News reported.

Over three-quarters of voters (77%) said they could back him and only 15% said they could not imagine themselves supporting him (net +59). Rubio announced his presidential bid in Miami in April.

Meanwhile, Bush earned slightly less impressive numbers than Rubio. Seventy percent of GOP primary voters said they could support Bush, but 27% said they could not (net +43). Although Bush has hinted at a potential presidential run in 2016, he has yet to make an official announcement.

Fellow likely presidential candidate Governor Scott Walker of Wisconsin also fared well. Fourteen percent of GOP primary voters chose Walker as their first choice, with another 13% choosing him as their second choice. According to NBC News, 61% of voters said they could support him, while 16% said they could not (net +45).

The poll found that 11% of voters chose Kentucky Senator Rand Paul, who has already announced his bid, as their first pick, with an additional 9% choosing him as their second pick. Fellow official nominee Senator Ted Cruz of Texas faired slightly worse. Eleven percent chose Cruz as their first choice, but only 7% chose him as their second choice.

Brand-new candidates Ben Carson and Carly Fiorina scored among the worst of the potential contenders. Seven percent of primary voters chose Carson as their first choice and another 4% chose him as their second. Fiorina scored the worst of all, with a mere 1% choosing her as a first choice and another 2% choosing her as a second choice.

The newly released poll also revealed that Bush, Rubio and Walker trail Democratic powerhouse Hillary Clinton in head-to-head contests. Clinton edges out Bush and Rubio 49% to 43%, while leading Walker 50% to 40%.