Washington (CNN) - Thursday's landmark Supreme Court decision upholding the country's health care law appears to have had exactly zero impact on the presidential election so far, and has produced virtually no change in opinions on President Barack Obama or Republican challenger Mitt Romney, according to a new national poll.
And while the CNN/ORC International survey released Monday indicates the president with a very slight three point edge over Romney among registered voters nationwide, the presumptive GOP nominee appears to hold an eight point advantage among voters who live in the 15 states considered in play in the race for the White House.
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But according to the poll, which was conducted in the four days following the high court's health care ruling, there's been a surge in enthusiasm by Democrats nationwide, and registered voters say that Obama would handle health care better than Romney.
In a general election showdown between the president and the presumptive GOP nominee, 49% of registered voters nationwide say that if the November election were held today, they would vote for Obama, with 46% saying they'd vote for Romney. The president's three point edge is within the poll's sampling error. The results are identical to the numbers from the last CNN poll, conducted in late May.
Obama's job approval rating in the White House, now at 51% (with 47% saying they disapprove), is virtually unchanged from the 52% he scored in our last poll, and the same is true of his personal favorability rating, which stands at 55%, with 45% saying they hold a negative view of the president. Romney's favorable rating, now at 48%, is also unchanged. Forty-two percent say they hold an unfavorable view of the former Massachusetts governor, who is making his second bid for the presidency.
About a third of all Americans live in states that are not considered safe Republican or safe Democratic strongholds, including toss-ups states (like Florida and Ohio) as well as states that lean toward one presidential candidate but could ultimately wind up voting for his rival. In those 15 "battleground states," the poll indicates that Romney currently has a 51%-43% advantage over the president among registered voters, if the election were held today.
"Note carefully that this does not mean that Romney will win each of those states by eight points, or that he will win all 15 of those states," says CNN Polling Director Keating Holland. "That's both good news and bad news for Romney. The good news: he has residual strength in states that the two campaigns are fighting over. The bad news: Romney is also spending resources defending states that should be part of the GOP coalition, rather than taking the battle to Obama's home turf."
The survey indicates that Romney clearly has a big advantage in some of those 15 states, but the data does not indicate which states he is currently winning or how big that advantage may actually be. Neither candidate needs to win all 15 of those states in order to win the general election, so the aggregate results from all 15 states do not forecast an Obama loss or a Romney victory.
The survey indicates the real effect of the Supreme Court's health care ruling may be in motivating voters rather than changing their minds, and the poll indicates that Democrats, for the moment, may be a bit more eager to vote than Republicans.
Fifty-nine percent of registered voters who describe themselves as Democrats say they are extremely or very enthusiastic about voting this year, up from 46% in March. Fifty-one percent of registered voters who call themselves Republicans are extremely or very enthusiastic about voting, unchanged since the spring.
Also working in the Democrats' favor: Registered voters say that Obama would handle health care better than Romney by a 51%-44% margin.
More than half of those questioned say the high court's ruling will not impact their vote for president. But three in ten say that the court's decision will make them less likely to vote for Obama.
"But more than half of those respondents are conservative and nearly nine in ten say they were already planning to vote for Romney. The same is true of the 16% who say that the court's decision makes them more likely to vote for Obama - more than nine in ten are already in Obama's camp," says Holland. "So the court's decision seems to have hardened existing opinions rather than changing them, making the fight for the dwindling crop of persuadable voters all the more important."
In any case, the election will not be held tomorrow - and one in five registered voters say they may change their minds between now and November.
The CNN poll was conducted by ORC International, from June 28-July 1, with 1,517 adults nationwide, including 1,390 registered voters across the country, and 534 registered voters in 15 "battleground" states, questioned by telephone. The survey's overall sampling error is plus or minus 2.5 percentage points.
– CNN Political Editor Paul Steinhauser contributed to this report