President Barack Obama on Wednesday will meet separately at the White House with Sens. Evan Bayh (D-Ind.) and Lindsey Graham (R-S.C.).

White House officials were not immediately available to comment on why Obama is meeting with the two lawmakers.

But Bayh is a key Senate Democratic moderate whose support for health reform will be crucial for the president as he seeks to assemble the 60 votes needed for a health care overhaul.

Graham has occasionally been known to buck his party’s conservative wing. But he joined the rest of the Senate Republicans in voting against allowing the Democratic health care bill to the floor and has vigorously opposed health legislation approved in the House.