Senate Minority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellGOP moves to cut debate time for Trump nominees McConnell hits back at 'ridiculous' Chinaperson remark GOP senator: 'We were there' on immigration before talks got derailed MORE (R-Ky.) and Sen. Rand Paul (R-Ky.) introduced a national right-to-work amendment to the Employment Non-Discrimination Act (ENDA). [WATCH VIDEO]

Their amendment — which likely will be blocked by Senate Democrats — aims to prohibit labor unions from forcing some employees to pay union dues.

“In practical terms, here’s what that would mean for middle-class folks in Kentucky and across America: If you want to join a union, you can. And if you don’t want to join a union, you don’t have to,” McConnell said on the Senate floor Tuesday. “That’s it.”

The Senate is expected to debate ENDA for the rest of the week. S. 815 bans workplace discrimination based on sexual orientation and gender identity. On Monday, the Senate voted 61-30 to end debate on a motion to proceed to the bill.

Senate Health, Education, Labor and Pensions Committee Chairman Tom Harkin (D-Iowa) said Monday that he hoped senators would file only germane amendments.

McConnell pointed out that nearly half of the states have right-to-work laws on the books and blamed unions for harming job creation and the economy.

“It’s basic fairness,” McConnell said. “This amendment isn’t just about ending institutional discrimination against workers; it’s also about job creation, economic growth, and making America more competitive in the 21st Century.”