As Mitt Romney announced his running mate on Saturday morning, recent polls have shown that incumbent President Barack Obama has increased his lead over the GOP presidential nominee. A new CNN International survey was released on Thursday that showed that 52% of the voters would vote for the President while just 45% would back Romney.

Last month, the same survey showed that Obama’s lead was three points over the Republican, 49% to 46%. The difference was within the plus or minus range of sampling error in the poll.

The most recent results fall in line with results from three different surveys that were released over the past couple of days. The average of all the polls shows that Obama holds a 49% to 43% lead over Romney.

Romney has had trouble trying to improve his popularity with voters over the past few weeks, with the polls showing that the presumptive presidential nominee’s unfavorable rating has started to rise.

Last month his rating of unfavorability increased from 42% to 48%. Meanwhile, President Obama’s favorable to unfavorable rating of 56% to 42% did not change over the same time period, said the new CNN International Poll.

The former governor of Massachusetts had been hit with persistent attacks from President Obama’s campaign and its supporters over the summer. Many of the attacks have been because of Romney’s financial portfolio, his lack of not wanting to release more tax returns and his business record and tenure while the president and CEO of Bain Capital. Romney’s campaign has also hit back at Obama with negative ads.