This Bloomberg piece has a lot of good data on which candidates benefit most and least from small donations. Some excerpts:
Democrats in Congress are trying to increase the clout of small donors, yet a provision in their voting-rights legislation risks favoring candidates from either party who hold polarizing views and widening ideological divisions on Capitol Hill….
“It will cause absolute chaos,” said Jim Moran, a former Democratic representative from Virginia. Moran, who served as mayor of Alexandria, Va., before entering Congress, said the legislation would give an advantage to inexperienced candidates. “This skips all of that traditional process and empowers people who have a provocative idea and can gain attention.”…
Less outspoken members of Congress, on the other hand, don’t attract as much support from small-dollar donors. Members of the Problem Solvers Caucus, a bipartisan group of lawmakers who try to craft balanced policy, raised just 9.5% of their re-election funds from contributors giving less than $200….
“If you think members of Congress were running scared of compromising, this’ll amp that up,” said Ray La Raja, a political scientist at the University of Massachusetts at Amherst. Candidates like Gottheimer, who raised $7.7 million with just 2.4% of that amount coming from small-dollar donors, would have to worry about better-financed opponents from the extreme right or left.
La Raja’s research has shown that small-dollar donors tend to be wealthier, better educated and more partisan than average Americans. “They are as ideological, if not more so on several issues, than large donors,” he said.