A liberal Democratic lawmaker on Thursday said that the public health insurance option could still be included in a final reform bill.

Rep. Keith Ellison (Minn.), a member of the Congressional Progressive Caucus (CPC), said that the government-run plan is within grasp a day after 7 additional senators signed on to a letter calling for Majority Leader Harry Reid (D-Nev.) to pass it through the Senate using the budget reconciliation process. 

He tweeted:

Progressive! Don't be discouraged; be ENCOURAGED. Public Option is within grasp if you ACT NOW! Call your Senator! Say: Support PO#!

Ellison's words underscore growing momentum among liberal lawmakers behind reintroducing the public plan after it was struck from the Senate bill late last year. 

House Majority Whip James Clyburn (D-S.C.) said Thursday that the public plan "could very well be" reinserted into the final bill, the strongest statement yet from a Democratic leader. 

Clyburn spoke after Democratic Sens. Diane Feinstein (Calif.), Roland Burris (Ill.), Al Franken (Minn.), Pat Leahy (Vt.), John Kerry (Mass.) and Sheldon Whitehouse (R.I.) signed the letter written by Sen. Michael Bennet (D-Colo.) and co-signed by Sens. Kirsten Gillibrand (D-N.Y.), Jeff Merkley (D-Ore.) and Sherrod Brown (D-Ohio).

Sen. Bernie Sanders (I-Vt.), who caucuses with the Democrats, also signed the letter Wednesday. 

"Although we strongly support the important reforms made by the Senate-passed health reform package, including a strong public option would improve both its substance and the public’s perception of it," the letter reads.