A domino effect or chain reaction is the cumulative effect produced when one event sets off a chain of similar events. The term is best known as a mechanical effect, and is used as an analogy to a falling row of dominoes. It typically refers to a linked sequence of events where the time between successive events is relatively small. It can be used literally as an observed series of actual collisions or metaphorically as causal linkages within systems such as global finance or politics. (Wikipedia)
In the fundraising process, the domino effect is usually result of a leading investor who invested into a securities issue and thus triggered a chain reaction from followers through the matching funds process.