State Senator and Pennsylvania Gubernatorial candidate Doug Mastriano is promising that, if elected governor, he would "reset" voter registration. That is, he would cancel ever Pennsylvania voter's registration, and make every single voter in the state register to vote anew.
The whole idea is nuts. I can't think of a clearer solution in search of a problem. But I also really wonder why Mastriano presumably thinks reregistering everyone is going to benefit Republicans. Republicans tend to be older than Democrats, and younger people, while often voting in lower proportion tend to favor Democrats. Pennsylvania is a state with a higher percentage of elderly than most other states, which means that the Republican votes in the state probably heavily rely on older voters. Requiring re-registration just adds another bureaucratic hurdle, a hurdle that older people (I would guess) would be less likely to clear than the average voting-age person. Meanwhile, people registering for the first time would continue to register at the normal pace. The Motor Voter law is still in effect, so young people getting their drivers license for the first time would have an easier time clearing that hurdle. They would just check a box when getting their license, while older people would have to make a special effort to re-register.
Obviously, no one can be sure how making everyone re-register to vote would pan out. I'm sure both parties would work hard to push their supporters to re-register and maybe a well-organized campaign on the Republican side could give them an advantage. But it's not clear that Republicans would have a better campaign than Democrats. And just based on the demographics of the state, it seems that the Republicans would go into a re-registration requirement with a bit of a disadvantage.