This week Democrats seized on two issues meant to broaden their popularity among working class voters: coal miners’ benefits and “Buy America” provisions in an infrastructure bill.

Leading the charge are red-state and Rust Belt Democrats like Manchin and Ryan and others from regions that Trump won by large margins. Trump won surprise victories in old industrial states that Obama won by large margins, including Michigan, Wisconsin and Pennsylvania. Sen. Heidi Heitkamp of North Dakota and Sen. Claire McCaskill of Missouri have been vocal, as well as Sen. Jon Tester of Montana. Many of them are up for reelection in 2018 and are in vulnerable seats.

In the Senate, they threatened to hold up a resolution to fund the government unless Republicans extend coal miners’ health fund for one year. Republican Senate Majority Leader McConnell wants to continue the fund, which was established in the 1940s, only until early next year. In the House and Senate, Democrats are protesting Republicans’ removal from a water infrastructure bill a “Buy America” provision that would require government contracts to use American-produced steel.

“We’ve got have ‘Buy America’ and we’ve got to have the miners,” Sen. McCaskill said heatedly on Thursday midday.