Ted Cruz, we argued in February, is the most underrated candidate in the 2016 field -- for the simple reason that he can make a strong play for solo ownership of the Tea Party "lane" of the primary electorate. If Cruz can carve out enough consistent votes from that group to stick around a while, we argued, his overall support could snowball as other candidates drop out. Other candidates, the theory goes, are in other, more crowded lanes in which they could split up the vote: Jeb Bush in the moderate/establishment lane along with a few others, Rick Santorum and Mike Huckabee in the Evangelical lane (which Cruz made a play for on Monday as well), etc.

But how big are those lanes? And who's dominating in which lane? Let's say there are five lanes:

  1. Religious voters
  2. Tea Party voters
  3. Very Conservative voters
  4. Moderate/Establishment voters
  5. Libertarians

We can dispatch with the last one first; there simply isn't a lot of reliable recent polling on the overlap of Republicans and libertarian philosophy. In 2013, the Public Religion Research Institute estimated that 22 percent of Americans are consistently or broadly libertarian, 43 percent of whom identify with Republicans.

One can also estimate the width of the Libertarian lane by looking at who turned out in New Hampshire in 2012. According to exit polling, 31 percent of voters indicated that they were moderate on social issues and conservative on fiscal ones, fitting the general profile of a libertarian-leaning Republican. But that's New Hampshire, which is arguably one of the most libertarian states in the country ("Live Free or Die," etc.).

In 2012, libertarian-Republican Ron Paul vacuumed up 10.7 percent of the overall primary vote, though some of that came after the nomination was settled. That might be the size of the electorate, but it also likely answers another question: Who can count on that support. Here's a hint: His last name rhymes with "Paul" ... in the sense that it is "Paul."

As for the other four, we can't talk about them without pointing out that our analogy has a rather large flaw. We develop these lanes as a rhetorical device, but the lines between the lanes are not clear. A certain percentage of the party identifies as a supporter of the Tea Party and is also evangelical. It is likely also Very Conservative. Where does that support lie? With that in mind, let's do our best to draw lines as clearly as possible.

Tea Party. Since its emergence in 2010, the number of Americans that identify with the Tea Party has slipped downward, according to Gallup. But it's still robust within the Republican Party. In the 2012 primaries, Tea Party supporters averaged about 61 percent of the electorate in key states according to exit polls. In a poll from Quinnipiac University earlier this month, Tea Party supporters comprised a smaller part of the electorate, at 22 percent.

(A note on the polling: Pollsters often weight polls according to turnout expectations, making this figure less reliable. Polls don't always get that right; actual turnout can vary from expectations, making the 2012 exits more reliable. We're including the one from Quinnipiac because it gauges current support.)

Evangelicals. We looked at this on Monday in the wake of Cruz's announcement. Voters calling themselves Evangelical have been about 25 percent of the general electorate consistently since 2004 in exit polls. In key 2012 Republican primaries, the figure was higher, at nearly 50 percent. Among Quinnipiac respondents, the number was 38 percent.

Moderate/Establishment. In 2012 primary states, 33 percent of the Republican electorate called itself moderate or liberal. Among Quinnipiac respondents, moderate/liberal Republicans were 34 percent of respondents.

Very Conservative. The 2012 primary exits had an average of 67 percent calling itself conservative, which about matches the Quinnipiac conservative/very conservative percentage of 66.

Let's change gears for a second. The reason we used that Quinnipiac poll is so we could see how each possible candidate does in each grouping, but it doesn't include support from Evangelicals. The table below breaks down support from each of the last four "lanes" above, excluding the libertarians. This is a) nationally and b) just one poll, so don't assume that this is predictive for next November. But if someone's going to own a lane, it should show up here.

Support from various Republican constituencies

The number in bold is the highest value in that "lane." Numbers add up to more than 100 percent because of overlap, which we'll get to in a minute.

Candidate Tea Party Evangelical Moderate Conservative
Bush 5% 15% 19% 14%
Carson 10 9 5 9
Christie 4 5 12 6
Cruz 12 7 5 7
Graham 0 0 0 1
Huckabee 14 12 7 9
Jindal 1 2 5 1
Kasich 1 1 1 1
Paul 9 4 6 5
Perry 2 2 2 1
Rubio 4 4 6 4
Santorum 0 0 2 1
Walker 26 18 5 25

Cruz doesn't own the Tea Party lane; he's in third. He doesn't own Evangelicals; he's sixth there. Scott Walker has the right. Jeb Bush has the middle. No one else has anything.

Now we can combine the two, displaying the width of the lanes and the amount of support candidates get from each.

This is where the overlap becomes important. To look at that, Scott Clement and Peyton Craighill from our polling team (without whom I couldn't have done this or most things) figured out the overlap in 2012 between the various groups. They pulled data from the exit polls in Iowa and New Hampshire and figured out that 92 percent of white evangelicals in Iowa were also in the "very conservative" group, and 75 percent were also tea party supporters. In New Hampshire, those two figures were 62 and 68 percent, respectively. Both, obviously, also overlap with each other. There are people who are cruising in three lanes.

People have competing interests. And they figure out a way to prioritize and reconcile those interests in their political decision-making, leavening the whole thing which a bit of personal assessments of the candidates. But anyway, back to our generalizations.

For the sake of this lane-assessing, let's ignore the overlap (at our eventual and inevitable peril). That gives us a field that looks like this, using the Quinnipiac numbers. (This adds up to 160 percent of the electorate, since the Tea Party and Evangelical numbers overlap entirely with the Conservative/not categories.)

That gray space includes a lot of people who haven't really made up their minds yet. Consider it passing space within a lane. It's what polling early in a crowded Republican field is bound to look like. Among Evangelicals, for example, more people don't know who they're supporting than support a particular candidate.

The question for Cruz -- and for anyone hoping to add a lane -- is how you solidify that support and, more importantly, make those people put voting for, say, a Tea Party candidate above voting for just a hard-right conservative one.

What's clear is that Cruz has work to do in locking down that lane.