Mitt Romney has broken through a key ceiling of support in the latest Gallup national GOP presidential poll.

Romney is the first candidate to hit the 40 percent mark in the poll, and now holds a 14 percent lead over Rick Santorum, who came in at 26 percent, followed by Newt Gingrich at 14 percent and Ron Paul at 8 percent.


On five previous occasions, candidates have tested the upper 30 percent range, only to fall back with the rest of the pack shortly after. Romney has tested that upper boundary three times, while Gingrich and Santorum have each been turned back once.

Romney’s rising support among Republicans nationally could be more than just statistical — the campaign has recently reclaimed the argument that the former Massachusetts governor is the party’s inevitable nominee, which adds a strong psychological element to the 40 percent breakthrough.

Romney landed another big endorsement on Wednesday when he gained the backing of former Florida Gov. Jeb Bush, an influential figure in the party. Bush made his announcement the day after Romney won a double-digit victory in Illinois's GOP primary.

 The confluence of events has many speculating that Romney has all but sewn up the party’s nomination.

 About half of the delegates needed to secure the nomination have been awarded so far, and Romney holds a more than two-to-one lead.

Still, Santorum is expected to win the Louisiana primary on Saturday, where he holds a double-digit lead over the field in most polls.