Rick Santorum still leads in Louisiana, but the three-quarters of voters there who think Mitt Romney will still be the nominee might be right. According to Gallup’s daily tracking poll, the former Massachusetts governor has the widest lead he’s had in weeks:

Romney has the backing of 40% of registered Republicans nationwide, while Santorum comes in with 26%, according to Gallup’s daily tracking poll.

The 40% threshold also marks the highest point ever for Romney (or any other candidate) since the daily survey began measuring support in early November.

The poll shows a six-point increase for Romney since Tuesday, the same day he won the Illinois primary. Meanwhile, Santorum dropped four points in the same time period.

So dies the myth that Mitt Romney can’t attract more than 25 percent of the vote? Perhaps it wasn’t a ceiling, but a floor, after all. That’s the most positive part of this poll — that Republicans might rally after all to whoever becomes the nominee even if that nominee is Romney.

Still, the news that trickles in day after day about Romney’s likelihood to be the nominee makes the primary significantly less interesting. The other candidates presumably wouldn’t stay in the race for no reason and, in Rick Santorum’s case, it’s safe to assume he still envisions a path to the nomination to himself. It’s a path that hinges on stopping Romney, though, and, right now, given the states that hold primaries in April, it’s hard to see how he’ll hoard enough delegates from Romney to force the national convention to be contested. He’ll win Louisiana, yes, but what next? Maryland, D.C. or Wisconsin, all of which hold primaries April 3? Romney leads Wisconsin by 13! The Northeastern locations of the majority of the April 24 primaries are also favorable to Romney. He’ll be strong in Connecticut, Delaware, New York and Rhode Island. Santorum will presumably be able to count on Pennsylvania.

If, after Alabama and Mississippi, the question was whether the nomination would be won by math or momentum, the question now is whether the primary can possibly be won without either.