Mitt Romney has pulled even with President Obama in the battleground state of Colorado, but continues to trail narrowly in Nevada, according to new NBC News/Wall Street Journal polls.
In Colorado, the Democratic incumbent and his Republican challenger each draw 48 percent of the vote. That's a significant improvement for Romney from September, when the NBC/WSJ swing state survey showed Obama leading by five percentage points.
In Nevada, Obama leads with 50 percent to Romney's 47 percent. That's a tiny uptick from September, when Obama had 49 percent to Romney's 47 percent.
Both telephone surveys were conducted by the Marist College Institute for Public Opinion from Oct. 23-24, after the final Obama-Romney presidential debate on Oct. 22. The Nevada poll of 1,042 likely voters carries a margin for error of 3 percentage points. The Colorado poll of 1,128 likely voters carries a margin for error of 2.9 percentage points.
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In both states, pluralities of voters said Obama had performed better in the debate. But it changed few minds, since more than 9 in 10 voters in each said they had selected a candidate earlier.
But in Colorado, at least, the new survey showed some benefit for the Republican challenger from the new, more moderate tone he began striking in the first debate on Oct. 3 in Denver.
Romney cut his deficit among women voters in half, to seven percentage points from 14 in September. Meantime, he expanded his lead among men to eight percentage points from five in September.
The former Massachusetts governor also made headway among independents in Colorado. He now draws 46 percent of their votes to 45 percent for Obama; in September, Obama led by 11 percentage points among independents.
Romney has also narrowed his deficit among women in Nevada, to six percentage points from 16 in September. But there, Obama has improved his performance with men, among whom he now leads 48 percent to 47 percent after trailing by 11 points in September.
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In both states, Obama is lifted by his dominance among Latino voters — two-to-one in Colorado, and three-to-one in Nevada. But Romney has improved his image, which is now narrowly positive in both states after having been narrowly negative in September. Voters divide evenly in both states over which candidate could better handle the economy.
Both states, carried in 2008 by Obama, are among the battlegrounds each campaign has been contesting most heavily. Colorado has nine electoral votes, while Nevada has six.
—By CNBC's John Harwood