Republicans could lean on congressional procedure to defy the will of voters. But if they try that, the Senate has a clear way to fight back

…the Senate will be under the control of the Democratic party when it convenes on 3 January regardless of the election. Of the 65 senators carrying over, 32 are Democrats, plus the two independents (Bernie Sanders and Angus King) who caucus with them, but only 31 Republicans will carry over.

That assures Democrats an initial 34-31 advantage in the Senate. Normally, that advantage would just be momentary if the Democrats don’t capture the Senate in November, but this will be anything but a normal year if Republicans try to take the House with bogus election challenges.