Poll: Ahead of GOP convention, presidential race in dead heat

(CNN) -- The latest developments in the presidential campaign -- such as Mitt Romney's selection of a running mate -- has little moved the presidential race, a new poll released Tuesday, August 21st.

This NBC News/Wall Street Journal survey -- conducted entirely after Romney's announcement that House Budget Committee Chairman Paul Ryan would join his ticket -- shows President Barack Obama at 48% and his Republican challenger at 44%. That margin is within the poll's sampling error of plus or minus three points.

The results are in line with the other two polls included in the latest CNN Poll of Polls, which averaged the three most recent surveys to find Obama at 47% and Romney at 43%.

And the NBC News/Wall Street Journal poll found that 62% of voters were "very interested" in the presidential race as the two parties prepare for their back-to back conventions, which begin with the Republican National Convention next week. On a 10-point scale, another 18% rated their interest level at an 8 or 9. Public interest grew between April and May, the survey showed, as the presidential race entered the general election phase.

Six in 10 registered voters included in the poll said the country was off track, while 32% said it was "headed in the right direction." Those numbers nearly mirror the poll's monthly results since January (with the exception of February, when this survey was not taken).

The president's approval ratings have also remained largely unchanged. This month, 48% approved while 49% disapproved of "the job Barack Obama is doing as president," the poll found. On foreign policy, he had a positive approval rating, but on the economy, a negative rating.

Views of Romney were split, the poll found: 38% gave him a positive assessment and 44% gave him a negative assessment. The six point difference is equal to the poll's sampling error.

The results of this poll have been largely unchanged since June of 2011. In each of the months since, the margin between Romney and Obama has been no larger than six points.

CNN's Poll of Polls, which includes the NBC News/Wall Street Journal survey, as well as Gallup's daily tracking numbers and a survey released conducted August 15-19 by Monmouth University shows the race in a dead heat since the announcement of Ryan on the GOP ticket. Obama stood at 47% and Romney at 43%.

The poll included 1,000 registered voters contacted between August 16 and 20.