According to poll guru Nate Silver, President Obama is emerging as the clear favorite in this election.

On Friday, we began to see reasonably clear signs that President Obama would receive some kind of bounce in the polls from the Democratic convention.

Mr. Obama had another strong day in the polls on Saturday, making further gains in each of four national tracking polls. The question now is not whether Mr. Obama will get a bounce in the polls, but how substantial it will be.

Some of the data, in fact, suggests that the conventions may have changed the composition of the race, making Mr. Obama a reasonably clear favorite as we enter the stretch run of the campaign.

On Saturday, Mr. Obama extended his advantage to three points from two points in the Gallup national tracking poll, and to four points from two in an online survey conducted by Ipsos. He pulled ahead of Mitt Romney by two points in the Rasmussen Reports tracking poll, reversing a one-point deficit in the edition of the poll published on Friday.

A fourth tracking poll, conducted online by the RAND Corporation’s American Life Panel, had Mr. Obama three percentage points ahead of Mr. Romney in the survey it published early Saturday morning; the candidates had been virtually tied in the poll on Friday.