Romney's Win: How Broadly Based?

"He's winning conservatives. He's winning Tea Party voters. He's winning men, women. He's winning Catholics, Protestants."

Men, women, Catholics, yep. But the rest of that comment today from the Romney campaign's communications chief, Eric Fehrnstrom, is worth a little scrutiny. Clearly Romney had a big win in Illinois. But there's room for debate about how broadly based it was.

While Romney won conservatives and Protestants, in reality there are distinctly different kinds of conservatives (very vs. somewhat) and Protestants (evangelical vs. non-evangelical) within the Republican electorate. Romney lost very conservative voters, he lost evangelicals, and he lost related groups (e.g., those strongly focused on shared religious beliefs and very frequent church goers). Similarly, he won Tea Party supporters, as Fehrnstrom notes, but on the strength of people who support the movement "somewhat." Strong supporters of the Tea Party split evenly - Romney 42 percent, Santorum 41, well within sampling error.

Further, as we noted in our exit poll analysis, Romney won Republicans in Illinois with $100,000-plus incomes, and those with college degrees, by wide margins. Those less well-off and less-educated divided far more closely between Romney and Santorum  (+3 Romney in both cases in the final data, again not significant at this sample size).

Romney did do better with evangelicals than his average (39 percent support in Illinois, vs. an average of 30 percent and a range from 14 to 62 percent). Nonetheless, if evangelicals and non-evangelicals voted exactly as they did in Illinois, but evangelicals matched their peak turnout, 83 percent, in Mississippi, the outcome would've been a dead heat, within polling tolerances: Santorum 43 percent, Romney 42. In that sense, comparing this week to last week, Romney didn't change minds so much as he changed states.

This works for him, in that few states look like last week's in terms of their proportion of evangelicals. But it doesn't mean he's won them over. Outside of Virginia (where his only opponent was Ron Paul), Massachusetts and New Hampshire, that hasn't yet happened.