BOSTON — After back-to-back presidential losses, Republicans in key states want to change the rules to make it easier for them to win.

From Wisconsin to Pennsylvania, GOP officials who control legislatures in states that supported President Barack Obama are considering changing state laws that give the winner of a state's popular vote all of its Electoral College votes, too. Instead, these officials want Electoral College votes to be divided proportionally, a move that could transform the way the country elects its president.

Republican National Committee Chairman Reince Priebus endorsed the idea this week, and other Republican leaders support it, too, suggesting that the effort may be gaining momentum. There are other signs that Republican state legislators, governors and veteran political strategists are seriously considering making the shift as the GOP looks to rebound from presidential candidate Mitt Romney's Electoral College shellacking and the demographic changes that threaten the party's long-term political prospects.