As the The New York Times detailed over the weekend, and as The Week's Matt Lewis predicted in July, a rivalry is brewing between Tea Party favorites Rand Paul and Ted Cruz. Each side is bad-mouthing the other, saying its rival is unelectable in the 2016 presidential race. Cruz reportedly trashed Paul as fatally linked to his extremist father, while Paul's aides call Cruz "the chief of the wacko birds."

Intraparty scraps are nothing new, and often the survivor emerges stronger. Barack Obama went the full 12 rounds with Hillary Clinton, and came out the other end battle-hardened. But for conservative insurgents hoping to take over the Republican Party from inside, a Paul-Cruz throwdown is the absolute last thing that they need, because it risks knocking them both out of the ring.

Many people assume that the right-wing ideologues in the Republican "base" dictate the outcome of their party's presidential primaries. That's not true. A movement conservative has not triumphed over an "establishment" candidate since Ronald Reagan in 1980.

There is a reason for that: Uncompromising conservatives tend to cling to their favorite candidates for too long, dividing their votes among several instead of consolidating their forces behind one. As the base splinters, the establishment's preferred (and always well-financed) choice is able to win early contests with relatively small pluralities. Party loyalty eventually kicks in, peeling off conservative votes and propelling the establishment pick to the finish line.

This is why Rush Limbuagh's 2008 tirades against John McCain could not make conservatives choose between Mike Huckabee, Fred Thompson, and Mitt Romney. Instead, McCain was able to take the pivotal South Carolina primary with a mere 33 percent of the vote. Nor could Limbaugh derail Romney in 2012. Conservatives fractured between Newt Gingrich and Rick Santorum, allowing Romney to win most contests with less than a majority.

Compare that to 1980, when Reagan was the only movement conservative facing off against a pack of establishment types. While George H.W. Bush was able to emerge as the most plausible alternative, Reagan was able to easily defeat him mano a mano.

I wrote back in May that Rand Paul had a solid shot at the 2016 GOP nod, despite being anathema to the "national security" wing of the party, because the 1980 dynamic could be replicated. Polling at the time showed Paul consolidating conservatives, with the establishment camp splintering between Gov. Chris Christie, Sen. Marco Rubio, former Gov. Jeb Bush, and others.

But that was before Ted Cruz became the Tea Party darling du jour, interrupting Paul's ascendency. Now it's a pileup at the top of polls. The most recent survey from Public Policy Polling shows an effective four-way tie between Paul, Cruz, Christie, and Bush. But take either Cruz or Paul out of the mix, and a four-way tie would become a Tea Party romp.

Which raises a serious question for conservative insurgents: How bad do you want to remake the party?

Are you prepared to organize behind a single candidate, even if you have a few quibbles of tactical or substantive disagreement? Are you prepared to pressure anyone who might stand in that person's way to stand down and put their principles ahead of personal ambition?

Or are you going throw away a rare moment of establishment weakness and repeat the same mistakes of the past? Are you going to give the establishment you loathe time to regroup and figure out to whom they should funnel their money because you couldn't collectively decide whether Cruz or Paul would strip down government the most?

The establishment's favorite is always going to have plenty of money, and plenty of prominent surrogates in the media validating his presidential bona fides. Any insurgency is an uphill battle, and it can't be won with divided leadership. If the Tea Party wants to overcome money and elitism with people power, either some of its leaders will have to voluntarily check their egos at the door, or its followers will have to force them to.