The charts above are from the ABC News / Ipsos Poll -- done latest on August 28th and 29th of a national sample of 732 adults, with a 3.9 point margin of error.
It shows the favorability of the candidates before and after their conventions. Joe Biden was viewed favorably by 40% of adults before the Democratic convention. After that convention, the number had risen to 45%. Donald Trump was viewed favorably by 32% before the Republican convention. After that convention, his favorability was 31%.
Joe Biden got a significant bump in how adults viewed him, but Donald Trump did not. The current difference in favorability is about 15 points for Biden over Trump. Biden has a 6 point positive difference in favorability (46% favorable to 40% unfavorable), while Trump has a 28 point negative difference (31% favorable to 59% unfavorable).
The same is true in the vice-presidential race. Kamala Harris got a big bump in favorability from the Democratic convention, while Mike Pence did not get a bump from the Republican convention. The current favorability in 43% for Harris and 31% for Pence -- a 12 point difference.
