WASHINGTON - US President Barack Obama enters an important campaign week tied with Republican presidential nominee Mitt Romney, a Reuters/Ipsos poll found on Sunday.

With the Democrats set to nominate Obama for a second term this week at the Democratic National Convention in Charlotte, North Carolina, the race to the presidential election on Nov. 6 is all knotted up at 45 percent for Obama and 45 percent for Romney among likely voters, the survey found.

A week ago, a Reuters/Ipsos poll said Obama led Romney 46 percent to 42 percent. The Republican's own convention last week in Tampa, Florida, gave him a small boost, vaulting him into an even position with Obama but no further.

Now Obama, who is to accept the nomination on Thursday, is poised to get his own convention bounce. Ipsos pollster Julia Clark said she was confident Obama's numbers would improve during his convention.

Please LIKE our Facebook page - it makes us stronger