Senators on the Rules Committee will hear testimony Tuesday on Ralston's plan, which would generally prohibit lobbyist spending on individual state officials, including lawmakers.
It contains several big exceptions. Lobbyists could still pay to wine and dine members of committees, caucuses or delegations. Lobbyists could also pay to send lawmakers on trips that are deemed related to their official duties. House lawmakers adopted that plan earlier this year.
The Senate has adopted an internal rule prohibiting individual lawmakers from accepting gifts worth more than $100 from lobbyists. Ralston has called that plan weak.
Senators must decide whether to approve the bill before the end of session on March 28.