The third Democratic debate is the first to feature all the major candidates onstage together. Since the Democratic National Convention made tougher rules for eligibility, only 10 candidates will appear.

The debate will be Thursday from 7 to 10 p.m. on Tulsa's ABC affiliate, KTUL, channel 1008 on Cox, 8 on DirecTV and Dish, and 1008 on U-Verse.

An ABC News/Washington Post poll released Sunday shows Joe Biden, Bernie Sanders and Elizabeth Warren leading the field of candidates. Biden had support from 27% in the Sept. 2-5 survey of 437 Democrats and Democratic-leaning independents. Sanders had 19% and Warren had 17%, after she shot up 6 percentage points from an early July survey, according to Bloomberg.