The business group that has been pushing for amnesty but that has often backed Republican candidates is throwing its support behind Democrats in several key House races this cycle. Among the Democrats endorsed by the Chamber is pro-amnesty TX Dem Rep. Henry Cuellar.
http://www.breitbart.com/Big-Government/2014/09/04/U-S-Chamber-of-Commerce-Endorses-Dems-in-Key-House-Races