They didn't even have to coax them, Obama just put the cuts up on the table himself. In 2011 when they were negotiating the budget, Ryan was offering zero cuts to social security & Obama decided to just throw in the cuts anyway,
"On Social Security: Ryan didn't cut Social Security by a penny. The president has proposed cutting the program's spending by $130 billion, by adopting a slower-growing measure of inflation."
"But his (Obama) cuts to Social Security and Medicare combined are somewhere between $200 billion and $380 billion deeper than the GOP budget."