In a move that could increase tensions inside Virginia’s Republican Party, Attorney General Ken Cuccinelli on Monday backed a transportation plan that rivals one introduced by Gov. Bob McDonnell and now threatens his fellow Republican’s legacy.

The plan Cuccinelli endorsed is being presented as a conservative alternative to McDonnell’s transportation package, which would eliminate the state gas tax and increase the sales tax and certain fees to raise $3.1 billion for roads, a top priority in vote-rich Northern Virginia.