The last time I ran for office, on election night I trailed by just two points and the gap seemed to be closing. But despite my optimism, my consultant told me that it was over. I was cooked. I didn’t believe him. I reminded him about the precincts not yet reporting, and the scenarios that would lead to victory. He wanted me to look at his spreadsheet, but I could see the numbers for myself and brushed him off.

As the evening waned, my election night party friends slowly trickled away, until just a handful remained. Finally, I sat down with the consultant and looked at his spreadsheet. It was over. I could see it with my own eyes. I got up, made brief remarks to the stragglers, and that was it.

In hindsight, it’s pretty embarrassing. Actually, it was embarrassing then, and profoundly sad.

It wasn’t just my own ego that kept me from conceding the race, or from even looking at the inexorable numbers. It was my sense of mission and my commitment to the many people who had worked so hard to elect me. You can’t just give up on it, or on them. If there’s any chance at all, you need to hang in there.

On Super Tuesday, I voted for Marco Rubio. I could have just as easily voted for Ted Cruz, but I chose Marco. He’s an inspiring young leader, with a grasp of policy, a vision for the future, and a willingness to innovate, try, fail, and try again. Before primary day here in Texas, I actually made a tiny donation to the Rubio campaign. I’m not much of a political giver, both from lack of excess funds, and the scarcity of donation-worthy candidates, but I gave a token of my support to Marco’s campaign.

Ted Cruz won Texas, and that was great. Still, I thought Marco’s pivot to challenge, and even to mock, Donald Trump was exactly the right way to combat a bully. I think it worked, just not for Rubio.

At this point (March 9, 2016), even if Rubio were to win his home state of Florida, he has no reasonable path to the nomination.

I say that as a man who’s not opposed to a so-called “brokered convention.” I call a brokered convention what it used to be called: an actual convention, in contrast to the kabuki coronations we’ve seen in recent years. The delegates would actually have a purpose — beyond drinking too much and eating too much — if they had to negotiate among competing factions and find a nominee all could rally around. It worked for Abraham Lincoln at the 1860 convention where he became everybody’s second choice, and then the nominee.

But Rubio is no longer everybody’s second choice. He’s third. He’s fourth. It pains me to say this — both because I like Rubio, and because I remember how tough it was to acknowledge my own defeat.

Marco Rubio is a patriot who wears his love for America on his sleeve. He often notes how he sees his public service as repayment of a debt that can never be cleared, since America has given so much to his family of Cuban immigrants.

Marco Rubio is a viable presidential candidate…but not this year.

Nevertheless, he can still perform a priceless service to this God-blessed country. He can join with Ted Cruz in preventing the nomination of an amoral autocrat whose protectionist policy proposals would trigger a great depression, and whose sociopathic personality would alienate our allies, making us less safe.

At this moment, this is the greatest service Marco Rubio can offer to his country. Later, perhaps, he’ll do even greater things.

Rubio has already served his country nobly by drawing attention to who Donald Trump really is. Now, it lies with Rubio — and perhaps with him alone — to ensure that such a scoundrel never sullies the office of the presidency in this nation which Marco Rubio loves so much.