Note: This is not an institutional endorsement. Each writer at Hot Air has their own conscience and freedom to decide on their favored candidate. This post reflects only my opinion, not those of my colleagues at either Hot Air, Townhall, or of Salem Media Group.

Several months ago, readers began peppering me and other writers at Hot Air about which Republican candidate we would support in the primaries. For my part, I have learned to wait until the vote takes place. Candidates drop out or make themselves unpalatable over the arc of a primary season, and this has been especially true for this cycle. The GOP boom in two-term governors turned out to be mostly a bust; Scott Walker’s lack of traction turned out to be one of the bigger disappointments of 2015. At various points, however, I have promised to disclose my choice when Minnesota holds its caucuses.

Tomorrow, that day arrives, but ironically, I won’t be there. My CPAC travel plans and Going Red promotion efforts require me to arrive in Washington DC early this week, and I will be out of town tomorrow night when the caucuses take place — and one has to be present to vote. Still, the spirit of that commitment requires me to make a choice and disclose it. And that choice is Senator Marco Rubio.

This was actually a very tough decision, and it came down to Rubio and Senator Ted Cruz. In fact, it was so tough that it took the most recent debate to make the choice. Both men have admirable qualities that make them good choices for the GOP nomination. Neither of them are perfect. Under the best circumstances, I would prefer a seasoned Republican governor with a solid track record of conservative policy accomplishments who could represent the future of the party. While Governor John Kasich has done well in Ohio, there are other reasons for reservations about his candidacy, especially his embrace of bad policy in the Medicaid expansion of ObamaCare — and the manner in which he lashed out at conservative critics of that policy. That leaves the two first-term Senators — both of whom arrived as conservative insurgents — as the best of the field.

Both Rubio and Cruz have had high and low points in Washington. Rubio’s low point came with the Gang of Eight bill, which he admits now was a mistake. Cruz led a poorly conceived shutdown over the fantasy demand that Barack Obama sign a budget defunding ObamaCare, which ended up leaving Republicans on the defensive in 2013 and nearly overshadowed a catastrophic failure in the program’s rollout. Neither of these mistakes did any long-term damage, but the two mistakes reflect a key difference between the two candidates. Rubio tried too hard to work with others and made a bad deal but eventually recognized that, while Cruz doesn’t work well even with members of his own party and makes the kind of impossible-to-keep promises that end up disillusioning voters.

One major reservation for supporting candidates in the Senate is that they don’t have a track record of accomplishment on which to rely. However, one accomplishment highlights the differences between the candidates most keenly on the issue of ObamaCare and demonstrates Rubio’s effectiveness in his Senate perch. Cruz led the aforementioned failed shutdown that accomplished nothing except a few news cycles that focused on closed facilities more than the epic HHS failure in October 2013. John Kasich has bought into ObamaCare with the Medicaid expansion. Donald Trump has praised the individual mandate against which conservatives have fought for years, and keeps going back and forth on single-payer health care.

Rubio, on the other hand, saw a way to block crony payoffs to the insurance companies that pushed for that mandate with the restriction on funds for “risk corridor” payments. Rubio demanded a rider on the 2013 “cromnibus” that blocked general-fund payouts under that program, limiting them to taxes collected specifically for that function. Rubio’s effort remains the only effective Republican legislative limitation of ObamaCare since its March 2010 passage, and the one that has pushed most of the government “co-ops” out of business.

While conservative policy would be served well by both men, the approach to conservatism and inclusion is perhaps the most important quality in my choice. Cruz, as solid a conservative as anyone could want in the Senate, has run his primary campaign on the basis of ideological purity. Cruz has repeatedly argued, especially in regard to Rubio, that he’s not just the most conservative candidate in the race but the only conservative in the race. That portends an insular, base-driven campaign that simply will not work in swing states any longer. The last base election success came in 2004, and that was in support of a wartime incumbent against a largely inept challenger. Rubio, on the other hand, has run a campaign predicated on broadening the party by selling conservative policies in communities largely ignored by the Republican Party over the last several decades. While Cruz could improve turnout performance in deep-red states with an ideological campaign, Rubio’s approach holds the most promise in states like Florida, Ohio, North Carolina, Colorado, and Virginia — states the GOP must win in November.

For those who look at a track record of taking on the “establishment,” both Cruz and Rubio offer hope. Both ran for the US Senate against the will of GOP leadership, and both won impressive victories. However, Rubio ran against popular incumbent governor Charlie Crist and beat him so badly in the primary that Crist left the party — and Rubio wound up winning 49% of the general-election vote in purple-state Florida in a three-way race, beating Crist by 19 points and Democrat Kendrick Meek by 29 points. Rubio won his Senate seat in a tough environment and in a key swing state for November, even while holding fast to conservative policies.

With all of that said, both Rubio and Cruz represent the future of the Republican Party and an opportunity to broaden the reach of conservatism. I would be happy to see either man win the nomination — but a choice has to be made. Marco Rubio gives Republicans and conservatives not just their best opportunity to win, but their best chance to effectively implement conservative policies by creating the best coattails down the ticket in November. That is why Senator Rubio is my choice for the primaries.