Some Democrats privately fear Clinton may have promised too much.

During her appearance this week in Nevada, Clinton said she would push Congress to pass a comprehensive immigration bill with “full and equal” citizenship for immigrants living in the U.S. illegally. 

That will be difficult to do with Republicans expected to retain control of the House.

Obama found himself in hot water with immigration activists during his first term when he failed to deliver on his 2008 campaign pledge to take on immigration reform during his first year in office. But some Democrats say Clinton may avoid the same fate.

“The issue back in 2008 was committing to a timeline,” said Jose Parra, a former senior adviser to Senate Minority Leader Harry Reid (D-Nev.) “So many things are out of the control of the president. She was smart not to offer up a timeline.”