Marco Rubio, opposing the budget-busting spending bill that worked its way through Capitol Hill, promised to use tactics to delay its passage but then he decided not to bother to show up to vote:

Republican presidential candidate Marco Rubio railed against the year-end budget and tax package, suggested he might slow down its inevitable passage and then skipped the vote Friday. The Florida senator was the only White House hopeful in the Senate to stay on the campaign trail and miss the vote. Republican rivals Sens. Ted Cruz of Texas and Rand Paul of Kentucky showed up to vote against the legislation, while Sen. Lindsey Graham of South Carolina backed the bill.

He had suggested in a Fox News interview Thursday that Republicans should "use procedures to force the slowdown and changes." The Republican leadership informed senators Wednesday night and again Thursday that Senate Majority Leader Mitch McConnell, R-Ky., was setting a time for the vote, but Rubio did not act.

His fellow presidential candidates have tried to make an issue of Rubio's missed votes. As of late October he had missed almost a third of votes this year, and he has only showed up to vote on a handful of days since then. He has not voted since Dec. 3, when the Senate passed a wide-ranging transportation bill and took a series of budget votes.

But Rubio has appeared confident in his decision. In an October debate, he cited missed votes by previous presidential candidates when Florida Gov. Jeb Bush tried to criticized him, suggesting he should resign and comparing his schedule to a "French work week."

He's so busy in Iowa, a state where his campaign infrastructure isn't much bigger than Mail Boxes Etc.,  trying to convince voters that Ted Cruz is as bad on illegal immigration as he is.  Rubio doesn't seem to defend his own record on immigration anymore, since it is so abysmal; instead, most of his energies are focused on telling voters that Cruz is bad like him.

Marco Rubio has had one term in the Senate, and his only achievement, if you can call it that, is his Gang of 8 amnesty bill.  Why this makes him a conservative, I don't know.  In fact, what I think you will see in the coming months as Bush, Christie, and Kasich drop out is that most of their voters will gravitate to him precisely because he isn't conservative.

It sort of makes you wonder about this missed vote.  Did he miss it because he simply didn't care, or because he actually agreed with this budget?  Since Rubio has never spoken out about budgetary issues before, there is no reason to believe that he is any more conservative on economic issues than he is on immigration.

This article was written by Ed Straker, senior writer of NewsMachete.com, the conservative news site.