Title 52 defines all the conditions of voting in the USA. In particular 52 USC 21081 specifies the voting standards and equipment states are currently required to use in any election involving federal officials. Since the federal government does it already, in theory, all Congress has to do is a pass a law that changes this regulation.

Note however, that if states break these rules, there must be a court that is willing to hold them responsible for it. At present, I don't believe our corrupt courts are up to the challenge.

Good question that SCOTUS really needs to clarify by mandate/precedent ASAP.

Though each State almost down to each county can make its own voting laws, ine law in the Constitution should still override this one piece; Voters Must Be Legal Citizens Period. The Constitution makes this clear in the 14th, 15th and 26th Amendments. Though… the Voting Rights Act has arguably shifted more powers to the States to regulate and allow their own State Citizen rights vs. Federal Voting Rights.

And these are all the current legal arguments being made State by State, and some County by County, especially in California, New York, and Michigan, that are causing legal uproars over Voter ID in whom gets to vote per what State or County by who’s ID needed or non-ID Law.

https://constitutioncenter.org/the-constitution/full-text

While the Constitution gives the States the provisional right to prescribe the "Times, Places and Manner of holding Elections for Senators and Representatives" -- provisional as described below in Article I Section 4 -- later in the document, Article IV Section 4 makes clear that the FEDERAL government has the duty to "guarantee to every State in this Union a Republican Form of Government", which is to say, to guarantee that elections are A) held and B) HONEST.

Vote fraud's entire purpose is to disenfranchise citizens, and the FEDERAL GOVERNMENT is Constitutionally charged with preventing such fraud, however it might be attempted or achieved.

Article I Section 4: Elections

The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof; but the Congress may at any time by Law make or alter such Regulations, except as to the Places of chusing Senators.

Article IV, Section 4

The United States shall guarantee to every State in this Union a Republican Form of Government, and shall protect each of them against Invasion; and on Application of the Legislature, or of the Executive (when the Legislature cannot be convened) against domestic Violence.

Dictionary definition:

republic | rəˈpəblik | noun

a state in which supreme power is held by the people and their elected representatives