(Reuters) - Billionaire environmental activist Tom Steyer said he is not yet prepared to back Hillary Clinton as the Democratic nominee for president and he would not rule out supporting her main rival, Bernie Sanders, if he beats her in the primaries.
One of the biggest Democratic donors, Steyer could help Clinton boost her standing among environmentalist activists who are a key constituency within the Democratic party. Clinton is locked in tight races with Sanders in Iowa and New Hampshire, which both have early nominating contests.