President Trump continues to war with congressional Republicans as 2020 comes to an end. On Tuesday, he responded to the House’s Monday override of his annual defense spending bill veto by calling GOP leaders “weak” and “tired.” He accused them of committing a “disgraceful act of cowardice.”

However, thanks to Bernie Sanders, Senate Majority Leader Mitch McConnell was not able to hold his own veto override on Tuesday, but will have to keep the Senate in session through the New Year’s celebrations in order to overcome the Vermont senator’s procedural objections.

Sanders’ gambit is pretty simple. He wants the Senate to vote on increasing the $600 individual checks in the COVID-19 relief bill to a more meaningful $2,000. The House voted to do this on Monday (with 44 Republican votes), and it has the support of both Trump and president-elect Joe Biden. Unless McConnell brings this to the floor, Sanders will object to any effort to bring the defense veto override to a vote.

In itself, Sanders’ move is little more than a dilatory inconvenience for McConnell, as he can file for cloture. But McConnell can’t avoid the politics. Seventy-eight percent of Americans support the larger $2,000 checks, and this combined with Trump’s advocacy has put so much pressure on Georgia senators David Perdue and Kelly Loeffler, who are facing  January 5 runoff elections, that both are now supportive.

When the Senate gaveled in at noon on Tuesday, McConnell was noncommittal about allowing a vote on the stimulus checks, but he blocked efforts by Sanders and Minority Leader Chuck Schumer to force the issue. If he relents at all, he’s likely to attach poison pills to the measure.

This would force the Democrats to object to a vote on the checks and remove some of the pressure. It would also allow Perdue and Loeffler to say they support $2,000 checks without ever having to actually vote for them. For these reasons, McConnell will probably opt to go with the poison pill maneuver rather than approve the checks. This will anger Trump, but increasingly McConnell doesn’t care what Trump thinks.

On the other hand, it’s not likely that Perdue and Loeffler will benefit. With Trump railing against gutless Republicans in Congress, it’s unclear why this will make Trump-supporting Georgians eager to vote for Republican senators.