I realize it is April Fool's Day, but I resisted the urge to write a prank column today. Because, instead, it is also the beginning of Baseball Metaphor Season! Yes, it is indeed "opening day" for the proper use of baseball terminology, no matter the subject at hand. Which is why I went for the headline I did, instead of something like "Rubio Waiting In The Wings" or "Rubio Enters Center Ring" or some such. But enough of this navel-gazing out in left field (ahem, sorry), let's just get on with it.

Senator Marco Rubio, Cuban-American from Florida, is now officially "on deck." He is idly swinging a practice bat back and forth, in anticipation of his first real major-league performance. This moment, it should be noted, has taken a long time to get here. Rubio was elected to the Senate, after all, in the Great Tea Party Shellacking Of 2010. He's had over two years in the Senate now but has yet to put his stamp of approval on any comprehensive immigration legislation, even though he treats it as his own private issue within the Republican Party. Rubio enjoys being seen as "working hard" on some sort of legislative breakthrough on immigration, but up until now, that breakthrough has never actually happened. There's a good reason for that, and the reason is that his fellow Tea Party Republicans (mostly over in the House) are quite content to have Marco Rubio "working hard" on an immigration bill, but they're never going to support anything he actually comes up with. By supporting Rubio "working hard" on the issue, they can conveniently do nothing and (they hope) defuse the issue among the voters.

Rubio must know this, which is why he never actually writes a bill. He complains loudly whenever any Democrat (especially the president) proposes anything, his stock line usually being: "We were all really working hard on the perfect immigration bill, and now Obama comes along and achieves what we said we were going to achieve, and we're really annoyed by that." This was on display yesterday, as Rubio made sure everyone heard him state that no bill exists yet among the "Gang of Eight" (or as I like to call them, the "DC-8"). This has briefly put the spotlight back on Rubio "working hard" once again, but this is about the last time this trick is going to work. Because the deadline for an actual bill is fast approaching, and will arrive next week.

This isn't a hard deadline or anything, merely self-imposed. The DC-8 gang has already missed a few of these deadlines, though, and both Pat Leahy (the committee chair who will move first on the bill) and President Obama have signaled that if there is no DC-8 bill soon, they are going to move on their own. So Rubio's moment in the sun is really just him stepping into the on-deck circle, in anticipation of what's going to happen next week. He can increase the tension over whether a bill will appear for one more week, but then that's going to be it. After that point, a bill will take shape whether he's "working hard" on it or not.

Rubio is walking a pretty thin line on the issue, and it will be interesting to see what happens when the DC-8 bill is unveiled. Most of the "big picture" details have already been leaked, but there will assuredly be plenty of details for various groups to denounce once the final language is examined. And, of course, there is a wing of the Republican Party who is going to scream "Amnesty!" no matter what the bill contains. This is what Rubio's been dreading all along: that he will not be able to convince the Republican Party to follow his lead on the immigration issue. Or, to put it another way, Rubio's going to be attacked by members of his own party -- always an uncomfortable thing for any politician.

Rubio's bigger problem is that he is quite obviously thinking hard about a 2016 run for the presidency. This is why he wanted to make immigration his own pet issue in the first place -- so he can show some Republican leadership skills. But any reasonable compromise he can reach on immigration with Senate Democrats is (almost by definition) going to be unacceptable to a large group of House Republicans. Beyond congressional politics, Rubio knows he's going to have to face Republican primary voters if he does make a 2016 run. And there's a whole lot of the Republican base that is downright xenophobic on the immigration issue. If Rubio is seen as some sort of traitor to the cause by attempting to lead House Republicans towards new thinking, then he's going to have a much harder time of it in Iowa, to say nothing of the reddest of red primary states. In baseball terminology, Rubio risks being caught in this pickle, dodging between the "bases" of the Republican Party.

The DC-8 bill (with some minor tweaking along the way, no doubt) will likely easily pass the Senate. Republicans in the Senate are smart enough and experienced enough to realize that the party's previous hostility to immigration reform is absolutely killing them at the ballot box -- a trend which will only get much worse as more time goes by. Senators have a much more national vision than House members, and so there are a lot of Republicans in the Senate who know that passing immigration reform is, at this point, almost a necessity for their party's future national electoral prospects.

House members have much different motivations -- they only have to keep a close eye on what people in their home district are thinking. Which means there are a lot of them who won't vote for any immigration reform short of mass deportation (or Mitt Romney's "self-deportation," perhaps).

The real question is going to be how loud they're going to howl, and what language they're going to use to do so. Alaska Representative Don Young has already proven that not everyone's going to be respectful in this coming debate. While it was indeed admirable to see the Republican leadership land on him with both feet after using the term "wetback" last week, there are bound to be some other negative things said in the next few months.

Which is where Rubio really does have a chance to shine. Marco Rubio could stand up strongly for immigration reform and take on the most extreme members of his own party over in the House, and show the entire Republican Party what their choices are going to be: reactionary anti-Latino demonization, or inclusiveness and avoiding going the way of the Whigs. That's a pretty tall order to fill, it should be noted.

But it could happen. Rubio could actually lead the Republicans out of the wilderness they've been inhabiting for approximately the last two decades. By doing so, he would be seen as a fresh new Republican leader, bringing youth, vigor, and a new way of thinking to a sclerotic Republican wedge issue that is now cutting the wrong way. If Rubio can reduce the "Amnesty!" faction to mere grumbles in the background, while the House passes the Senate bill with Democratic and more-moderate Republican support, he will have achieved a revitalization of his party's chances among the fastest-growing American voter demographic.

I have no idea what the chances of that actually happening are, though. Nobody really does, because Rubio is untested in such actual leadership. He's great at projecting the image of "working hard" on the issue, but he's never actually had to defend a concrete proposal before this point. Of course, he could just torpedo the whole DC-8 effort -- that's still a possibility too. But if next Monday rolls around and the news of the day is the new DC-8 plan, then Rubio is going to have to put down the practice bats and step up to the plate. It'll be interesting to see what happens next. Will he knock it out of the park, or go down swinging?

"Hitting next for the Republicans, it's rookie Marco Rubio at his first big-league plate appearance.... Batter up!"

-- Chris Weigant

Cross-posted at The Huffington Post

Follow Chris on Twitter: @ChrisWeigant