More than 1 million Californians have registered to vote at the presidential election since Sept. 5, raising the state's voter registration to an all- time high of 17.3 million, election officials said on Sunday.
This was up from 16.6 million in the 2004 presidential election, which saw a 76 percent turnout.
California Secretary of State Debra Bowen said "voter interest in this historic election is enormous, and I expect to see a record of Californians cast ballots on Tuesday."
Nationwide, about 13 million people have already voted early and 9 million newly registration people are expected to vote in the historic election, placing additional strain on the nation's voting system.
In the Greater Los Angeles area, registration now stands at 4.3 million, also a record high, and up more than 350,000 voters from 2004, Los Angeles County Registrar-Recorder Dean Logan said.
Logan said he expected a turnout exceeding the 79.1 percent from four years ago. That means about 3.4 million votes will be tallied in the Los Angeles area alone on Tuesday night.
With official turnout estimates exceeding 80 percent, voting rights advocates demanded that Los Angeles officials print and rush printed ballots to every precinct to ensure that a 100 percent turnout could be accommodated.
Logan appealed to voters to cast their ballots between 9-11 a.m. and 1-4 p.m. on Tuesday to avoid lines that could last several hours at peak voting times.
Logan said so many voters are calling his office with questions that "the phone companies are telling us it's equivalent to what happens when there is an earthquake, and it jams the phone lines."
Elections advocates sent a letter to Logan demanding that sufficient ballots be printed tonight and Monday to handle every inactive and active voter who might present themselves to vote Tuesday.
If turnout exceeds 80 percent, as expected, 3.44 million Los Angeles County votes will be cast.