US President Barack Obama has gained a six point lead over Mitt Romney, the Republican presidential rival, a latest opinion poll has said.

The poll by CNN yesterday shows that Obama gained four points after the last week’s Democratic national convention in Charlotte, North Carolina, where he was re-nominated as the party’s presidential candidate for the November 6 elections.

Before the convention — September 4 to 6 — Obama had a lead of just two per cent over Romney.

According to a CNN/ORC International Poll released yesterday, 52 per cent of likely voters nationwide back Obama, compared with 46 per cent for Romney. Just before the convention, the two were tied at 48 per cent each.

“The Democratic convention was fairly well received, particularly in comparison to the GOP meeting the previous week in Tampa,” CNN Polling director Keating Holland said.

According to the CNN, the convention energised — at least temporarily — the Democratic base, as more Democrats (59 per cent) than Republicans (57 per cent) seemed to be enthusiastic about voting. This marks a turnaround from last week, when the number of Republicans who said they were extremely or very enthusiastic about voting was six points higher than for Democrats, the news channel reported.

However, according to RealClearPolitics, which keeps tracks of all the polls, an average of all the recent national polls shows that Obama now leads Romney by 2.9 points.

According to another poll conducted by Investor’s Business Daily/Christian Science Monitor/TIPP, Obama leads over Romney by two per cent; while Gallup says that the incumbent has a lead of five points over his Republican challenger, so does Rasmussen poll.

Interestingly in North Carolina, where the Democratic National Convention was held, Romney leads by a substantial 10 points.

The CNN said this year’s Democratic event wiped away some of Romney’s gains on personal qualities. The Republican nominee’s favourable rating increased to 53 per cent after the GOP convention, but fell to 48 per cent one week later after the Democratic event. Meanwhile, Obama rose to 57 per cent in the last week, his highest mark since 2010.

Results of these polls came the day on which the pollster for the Romney Campaign in a memo said that the Republican presidential candidate would win the November elections.

“The combination of having the superior candidate, being in a margin-of-error race with an incumbent President, having a cash advantage, and having an unprecedented grassroots effort and a winning message on the economy ensure that Americans will make a change in leadership in Washington on November 6,” Neil Newhouse, Romney for President Pollster, said in a memo released yesterday.

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