The Texas House gave tentative approval to moving the state's primary elections from March to February.
That would give one of the country's largest states a greater say in nominating presidential candidates.
The bill needs another final vote, likely today, before it goes to the Senate. House Speaker Tom Craddick has said the measure has support in that chamber.
Republicans and Democrats endorsed the proposal, which would make the 2008 primary elections February Fifth. Under current law, primary elections are held on the first Tuesday of March.
The legislation also would move the primary runoff date from the second Tuesday in April to the second Tuesday in March.