By Aruna Viswanatha WASHINGTON (Reuters) – Americans convicted of fraud and other white-collar crimes gained a new defender on Wednesday as an advocacy group that has long fought strict drug sentences launched a campaign pushing for lighter punishment for financial crimes. The advocacy group, Families Against Mandatory Minimums, contends that sentences in cases of fraud, insider trading and other economic crimes are sometimes excessive and inconsistent. Defense lawyers and some federal judges have pushed for lighter sentences for white-collar offenses, but many consumer advocates and members of Congress have faulted the U.S.