Clinton does especially well among women, and particularly among white women, one of her core support groups, in Ohio.
Obama makes more inroads among white women in Texas (39 percent support), though not up to his unusual 47 percent support from white women in the Wisconsin primary Tuesday.
Hispanics are key in Texas; they favor Clinton by 59-36 percent, about the same as the average in exit polls across all primaries to date (61-35 percent).
By contrast, it's a much closer 50-46 percent contest among whites in Texas, while African-Americans there are favoring Obama by a 4-1 margin, 76-18 percent.
That, too, resembles the outcome in all primaries to date (79-17 percent for Obama among blacks), but it's lower than some of his high-water marks, including his 91 percent support from blacks in Wisconsin.
Obama continues to do better with college graduates (who are less numerous among likely voters in Ohio than in Texas), with higher-income voters (also less numerous in Ohio); and with younger voters, particularly in Texas, albeit not at the level he achieved in Wisconsin.
He leads by 59-39 percent among those under age 40 in Texas; Clinton comes back with 60-25 percent support among seniors there. Seniors also are her best age group by far in Ohio, 57-33 percent.
Eleven percent of seniors in Texas are undecided, more than in any other group. But among likely voters who have a preference, it's the younger people in Texas who are most apt to say they may change their minds — 29 percent of under 40s. (And about as many in Ohio.)
The age gap shows up other ways.
Texas seniors are much more apt to say they'd be "very satisfied" with Clinton rather than Obama as the nominee; young people are more likely to be "very satisfied" with Obama. There are similar divisions by race. (In Ohio there's less of a gap by age, but a somewhat bigger one by race.)
A quarter of likely voters in Ohio are from union households; they back Clinton by 53-37 percent, as opposed to a narrower 49-45 percent division among those from non-union households.
Clinton lost union household voters to Obama in Wisconsin, though across all primaries to date she's won them by 50-43 percent. There are very few union voters in Texas.
Political allegiance also counts for much.
Clinton leads among party regulars in Ohio (55-39 percent) and Texas (53-42 percent) alike; Obama owes his competitiveness to independents who intend to vote in these open primaries. He leads among independents by 53-39 percent in Ohio and 53-40 percent in Texas.
Those are similar to previous primaries this year: Clinton's won Democrats overall, by 50-44 percent; Obama's prevailed among independents, 53-37 percent.
There's a difference on issues between these states: The economy and health care rank about evenly as the most important issue to Democratic likely voters in Ohio, cited by 34 percent and 30 percent, respectively.
In Texas, 33 percent cite health care, with the economy second, 22 percent.
Though demographics and personal attributes matter more, issue priorities do divide voters somewhat; in Texas, Clinton is supported by 53 percent of those who cite health care as their No. 1 issue, and 51 percent of those who cite the economy, versus just 39 percent of those who say it's Iraq.
Clinton's lead among economy voters in Ohio, 52-37 percent, is bigger than her lead overall; that's not so among health care voters.