If Tuesday’s debate could break in any number of directions, what may be resolved is the overall mood of Democratic primary voters, and whether they are more inclined to seek a politically cautious nominee who promises to restore normalcy in Washington, or a more confrontational standard-bearer with an ambitious and disruptive reform agenda. It is candidates in the latter category who now control the bulk of the financial might in the race, and are best positioned in most of the early primary states.

Anna Greenberg, a Democratic pollster who is not aligned in the primary, said an “anti-establishment” current had plainly taken hold, with voters rewarding candidates for defying the conventional limits of political debate and “pushing boundaries in really productive ways.” She pointed not only to Ms. Warren and Mr. Sanders but also to former Representative Beto O’Rourke, who has embraced a new political identity for himself as a gun-control activist and a critic of his own party’s relatively cautious platform on the issue.

“Across the board, whether it’s Beto talking about assault weapons or Warren and Sanders talking about Wall Street,” Ms. Greenberg said, “it does feel like there is a shift in the party that is kind of new.”