Sen. Bill Nelson plans to attend at least some of DNC in Charlotte, his office says.

A number of other Democrats across the country have opted to skip, not wanting to draw to close a tie to President Obama as they face tough re-election battles back home. Some say they just can't spare the time off the campaign trail.

The AP reported: Sen. Claire McCaskill of Missouri is the highest-profile Democrat to announce she'll skip the September shindig in Charlotte, N.C. At least 11 Democratic incumbents and front-running challengers will be no-shows, according to a count by The Associated Press.

All hail from conservative-leaning or toss-up states where President Barack Obama, whose speech accepting the party's presidential nomination will be the climax of the three-day convention, could be a drag on down-ballot Democrats.