Nationwide, American voters are split right down the middle over support for Obamacare - 41% in support, 43% in opposition. But, as is always the case, the "internals" of the new Zogby Analytics poll tell a far more intriguing story. The new Zogby Analytics poll 893 likely voters was conducted online on May 2 and 3 and has a margin of sampling error of +/-3.3 percentage points.

The chief supporters of the Affordable Care Act are the voters most essential for President Barack Obama and his fellow Democrats this November. First Globals, i.e. voters born between 1979 and 1996, support the new law by a factor of 45% to 35%, with 20% undecided. They provide the highest level of support of any age cohort. Opposition increases with age - Nikes (born 1964-1978) are almost split with 40% supportive and 41% opposed; Woodstockers (1946-1964) are opposed 45% to 40%; and Privates (1926-1945) solidly opposed 59% to 34%).

Democrats are supportive 65% to 17% and so are liberals (75% to 14%). Moderates back the law (45%-33%) and, significantly independents are now about even on the issue with 37% in favor and 40% opposed. Three in four Republicans and conservatives are opposed.

African Americans back the ACA 65% to 24% as do Hispanics, 65% to 11%. Whites are opposed 55% to 34%. Catholics tend to support it 47% to 41%. NASCAR Fans, Investor Class, and the Creative Class are tilt in favor.

In other words, it is easy to see why the GOP is backing away from favoring repeal of Obamacare as a campaign issue. In simple practical terms, by Election Day there will be perhaps as many 15 million newly covered Americans and promising to take away a benefit is political suicide. By the fall, premiums will have been paid by a huge majority and coverage and service will have kicked in. Most importantly, the new beneficiaries will be younger, non-white, and already inclined to support Mr. Obama. Angering them will be an invitation, not a deterrence, to their voting.

Even further, there is strong support for the key provisions of the bill that the Zogby Analytics poll tested. Nearly seven in ten (69%) support the ACA provision that Americans 26 or less can stay on their parents' health care plan. Only 18% oppose this. Sixty percent of Republicans and 67% of independents join the 79% of Democrats who support this provision. A majority of Privates (54%-36%) also back this, as do 67% of Born Again Christians.

Support is equally strong for the law's provision that prohibits insurance companies from denying coverage for people with some previous health problems. Again the majority is very large - 67% to 23%. And again the support is across the board: Democrats (71%), Republicans (61%) and independents (66%); 61% of Privates and 59% of Born Agains.

Not surprisingly, the one troubling piece of the ACA for Democrats is the so-called individual mandate, the part of the measure that mandates that individuals obtain health insurance or face fines. Only 28% support it while 58% oppose it. Democrats find themselves evenly split (41%-41%), while majorities of Republicans (14% support, 79% oppose) and independents (25% support, 57% oppose) are in opposition.

But the poll shows clearly why the political dynamics around the ACA have changed. The President has to rally his base to get them out to vote. Can he? He certainly influenced a lot of young voters in the closing days of enrollment to sign up for coverage.

The GOP cannot push for repeal without encouraging some Democrats to turn out. And if they try a "mend it, don't end it" approach, they risk losing elements of their own base. This is not suggesting that the Democrats are not in trouble heading into November - but it is to suggest that so is the GOP.