After months of gassy media speculation about Jeb Bush, Marco Rubio, and Chris Christie, we’re all near the point of dismissing deus-ex-machina rumors about candidates out of hand.

But this one … doesn’t seem so far-fetched.

A Texas pol who is close to Perry has been telling a few key strategists that the nation’s longest-serving governor sees a vacuum and is waiting to be summoned into the race. This source believes that could happen by late summer. Without fellow Southerners Haley Barbour or Mike Huckabee in the race — and with Newt Gingrich’s early troubles raising further doubts about the current lineup — there could be a glaring niche for Perry to fill.

According to another well-connected Republican, at least one Perry confidant has been very quietly making inquiries about the political terrain in the nation’s first voting state of Iowa. A third Perry associate, RCP has learned, has been heralding a small contingent of Iowans with the time-tested line that is often used by would-be candidates who are leaving their options open: “Keep your powder dry.”

Perry’s aides have long made it clear that the tough-talking Texan, who succeeded George W. Bush in Austin in 2000, would not seriously entertain the idea of mounting a White House run before the state’s legislative session finishes at the end of this month. That date is now less than two weeks away, and the 2012 presidential field remains fluid…

Perry’s presidential prospects may ultimately be contingent on the decision made by the only GOP White House hopeful who can boast a resume and home state that is large enough to mess with Texas: former Alaska Gov. Sarah Palin. Perry shares Palin’s dexterity with the simple, tough-talking language that tends to fire up the tea party faithful and is similarly adept at connecting on a human level that comes across as decidedly anti-politician, despite his more than a decade in the governor’s mansion.

His aides strenuously deny it, of course. Still, why not Perry? He has more than a decade of experience leading one of America’s biggest states, can boast economic growth at a moment when voters are desperate for relief from the malaise, would enjoy key regional support as a southerner, has budget-cutting cred to spare that’ll please tea partiers, and flashes enough personality to make him easily stand out at debates against other top-tier candidates like Romney, Pawlenty, and Daniels. If Michele Bachmann is confident enough of her chances in Iowa to run (“This is now beyond speculation. They are doing this.”), Perry might as well give it a go too. His concern, I guess, is that if Palin follows him into the race, she and Bachmann will siphon off enough votes on the right to make a lesser-known name like his unlikely to win any primaries. But to some extent that’s a self-fulfilling prophesy: The surest way for him and other grassroots favorites to discourage Palin from running is to jump in ASAP and start claiming votes (and political operatives in primary states) whom she’d need to boost her chances against the Romney/Pawlenty/Daniels centrists. That’s always been Bachmann’s strategy, I take it, that the surest way to avoid being stomped by Palin among tea partiers is to claim enough of her niche early that she decides to pass on the race. Perry would be even more formidable. But the longer he waits, the riskier it is.

Ed e-mails to say that he’s been expecting Perry to make a national move for a long time now and points to his unusual penchant, as a governor, for engaging on national issues. His candidacy does make a lot of sense. Tick tock.