Proponents who want to cap lobbyists' gifts to Georgia lawmakers hit the road Tuesday on a 13-city bus tour to promote their cause.

The tour precedes the July 31 primary, when ballots for both Republicans and Democrats will include a nonbinding question about ending unlimited spending by lobbyists on gifts.

No cap exists currently for the Georgia Legislature. Lobbyists spend about $1.6 million a year, mostly on food, trips and event tickets for lawmakers, drawing the ire a disparate and vocal alliance of groups that include Common Cause Georgia, Georgia Watch and the Georgia Tea Party Patriots.

The tour ends Friday in Athens.