"It has come to our attention that House leadership is contemplating bringing up the children's health care plan for another vote (Thursday)," the lawmakers wrote. "Unfortunately, many of us are in California now trying to help our constituents and would be unable to take part in such a vote."
Democrats have scheduled a vote Thursday on the tweaked version of a bill President Bush vetoed earlier this month to expand a popular state-run children's health care program for low-income families not covered by Medicaid.
Republicans sustained his veto last week, but members of the minority need many of those votes to prevent Democrats from securing a veto-proof margin.
The 13 southern California Republicans who signed the letter appealed directly to their homestate colleague's local prerogatives - "as a fellow Californian" - by thanking her for her remarks earlier in the week sympathizing with victims of the wildfires.
No Democrat signed the letter.
"We ask you to please reconsider any such scheduling decision," the Republicans wrote. "Members should not have to choose between making an important vote in Washington or being in California helping our constituents to get the aid they need to rebuild their homes and their lives."
Bush declared California a federal disaster area Wednesdayafter a late-night appeal from Republican Gov. Arnold Schwarzenegger, and he plans to tour the damage Thursday.