Pretty sure I know what Rubio fans will say to this, although Phil Kerpen’s idea is worth promoting anyway. Partly that’s because Rubio fans themselves seem perpetually impatient for supporters of other candidates to ditch their guy already and unite behind The Candidate Of Light And Hope, and partly because Kerpen’s sentiment ably captures the state of panic right now among anti-Trumpers. Not a single vote has been cast anywhere — and yet we may be mere days away from Trump effectively locking up the nomination, or so the narrative goes.

The time for voting one’s conscience is over before it began. The time for voting strategically is now:

It seems to me that if you want to stop Trump you have to support Cruz in Iowa even if you like Rubio over Cruz.

— Phil Kerpen (@kerpen) January 26, 2016

Any true blue Rubio fan in Iowa would be nuts to do that knowing how heavily Rubio’s depending on a good showing there to boost him in New Hampshire. If he finishes a strong third with 20+ percent, he’s got something to build on. If he finishes a distant third or, heaven forbid, fourth, he’s a paper tiger whom the media will place on life support as NH gears up to vote. The only way it’s worth voting strategically for Cruz in Iowa for Rubio fans is if some deal could be brokered in which Cruz supporters in New Hampshire then turn around and vote strategically for Rubio there, an arrangement which would probably finish off Trump but which is obviously undoable.

Even if it were doable, arguably Rubio fans in Iowa would still be better off sticking with their guy instead of backing Cruz for fear that, by boosting Cruz over Trump, they’d be setting Rubio up to face a more formidable opponent in South Carolina and beyond. The greatest irony of this primary is that Trump has led basically wire to wire in every state and national poll and yet every candidate remains convinced that the one infallible path to the nomination is to somehow end up in a one-on-one race with him. That’s Jeb’s strategy in attacking Rubio as a flip-flopper. That’s Cruz’s strategy in attacking Rubio as pro-amnesty. That’s Rubio’s strategy in attacking Cruz as weak on defense and cynically calculating in his policy stances. Make yourself the only alternative to Trump, the theory goes, and you’ll win with the 60 percent of the GOP electorate that’s still kinda sorta conservative-ish. If Cruz could maneuver Trump into a true one-on-one in Iowa, with Rubio and Ben Carson and Huckabee and Rand Paul no longer picking off votes, he’d win, or so the argument goes. Maybe we’ll see that theory tested on Monday night: Given all the “Trump versus Cruz” two-man-race hype lately, Iowans who are inclined towards another candidate must already be toying with the idea of voting strategically. Rubio fans are probably the exception since he needs a good showing in Iowa, but if you’re with Christie or Kasich or Santorum or Fiorina right now, you may end up treating the vote on Monday as a de facto Trump/Cruz referendum. That’s another huge X factor in Iowa polls alongside Trump’s unknown ability to turn out first-time caucusgoers. How many voters who are supporting someone else this week will grudgingly decide over the weekend that they can’t stand Trump — or Cruz — and have little choice but to vote for the other guy on Monday night? Never before that I can remember has Iowa had two guys at the top of the polls who are so passionately disliked by very different segments of the party.

Meanwhile, adamantly anti-Rubio Ace makes the case that if you’re undecided between Trump and Cruz in Iowa, you should vote Cruz partly because it hurts Rubio in New Hampshire:

If Trump just wins in NH and Iowa, Cruz is not much of an alternative, and that means that someone like Rubio will probably rise to be Trump’s main competitor.

Keeping Cruz in the race keeps Rubio, or some other Establishment stalking horse, out of it…

In addition, you’re going to want to keep Trump dishonest. Right, I said dishonest, because I have no illusions he’s really a conservative. I’m okay with that, as long as we can force him to stay dishonest, and stay in his current pretend mode as a conservative.

Trump is going to run to the middle, in all likelihood, as soon as he can. You’re going to want him to continue to having to play to the right, to make as many specific promises as we can wring out of him, before he runs to the middle.

Cruz is your best hope for that — so even if you support Trump, assuming you’d like the conservative version of Trump he’s currently selling you on, you’re going to want Cruz forcing him to stay to the right.

If you’re a populist and a border hawk, a two-man race for the nomination between Trump and Cruz is better than a three-man race between Trump, Cruz, and Rubio and much better than a two-man race between Trump and Rubio. And the way to maximize the odds of that Trump/Cruz race is for Cruz, not Trump, to win Iowa since Trump’s probably going to win New Hampshire anyway. I don’t get the argument about Cruz dragging Trump to the right, though. Even if it were true, Trump will still run to the middle the moment Cruz is eliminated. What good does it do conservatives to have Trump spend a few more months making promises to the right when he’ll pay no penalty for breaking those promises? And why would Trump continue to run right-ish against Cruz when he’s already talking up ethanol and gladhanding Pelosi and Schumer in Iowa? If this is how he sounds before a famously conservative electorate voters, imagine how he’ll sound before the California primary regardless of whether his opponent is Cruz or someone else. Trump is going to run as hard to the middle as he wants whenever he wants because he’s convinced that Republican voters won’t hold him accountable. And between the hardcore cult-of-personality Trump fans and the rest of the party who’ll tolerate him saying anything in the interest of beating Hillary, he’s completely right. Vote Cruz in Iowa because you like Cruz or, as Ace says, because you want to maximize the number of populists who can win the nomination, not because you think it’ll have any meaningful effect on what Trump will do as president.

I’ll leave you with some good news and bad news for Rubio fans. The good news: He finished first in the new ABC/WaPo poll at 23 percent when Republicans were asked who their second choice was, meaning that he really does have room to grow as candidates drop out. The bad news: The last two polls of New Hampshire tracked by RCP have him in … single digits. His polling average, which stood at 14 percent there on January 8th, is down to 10.5 now whether from the sheer weight of Jeb Bush attacks ads being piled on him or his own lack of luster. Put those two data points together, though, and you see clearly why few Rubio fans in Iowa will be taking Kerpen’s advice, even though Trump will benefit. Rubio needs a big bolt of good news to get him moving in New Hampshire and, barring an unlikely eventuality like him totally dominating the next two debates, a strong showing in Iowa is probably his only chance. Unless and until Mitt Romney endorses him, I mean.