Mayor Bloomberg could create “electoral chaos” if he runs for the White House as a third party candidate, according to a pollster.

If Mr. Bloomberg were able to win the popular vote in several states, he could end up denying one of the major party candidates the Electoral College majority needed to win the presidency, a public opinion pollster, Scott Rasmussen, said. Mr. Rasmussen’s firm recently found that 27% of voters surveyed would be likely to vote for Mr. Bloomberg.

“These numbers suggest that if Bloomberg can find a message that resonates, he might win some states and deny either major party candidates a majority in the Electoral College,” Mr. Rasmussen wrote on his Web site last week. “He could throw the Electoral College into a deadlock by winning enough states to ensure that neither the Republican nor the Democrat had a majority,” he added during a telephone interview yesterday.

If none of the 2008 presidential candidates secures an electoral majority, the Constitution mandates that the House of Representatives make the decision. From there, things get tricky: Rather than a straight vote of the 435 representatives in the body, where Democrats have a 36-seat majority, each state delegation gets one vote. Democrats currently have control in 26 states. If they were to lose control of one state, they would lose the majority.

Political analysts were quick to respond to Mr. Rasmussen’s political breakdown. An analyst at RealClearPolitics, Jay Cost, said Mr. Bloomberg would not have enough support in the House because many districts are gerrymandered to ensure the dominance of one party.

Still, he said, “as somebody who enjoys political oddities, it would be very interesting to see an election decided by the House.”

The House of Representatives has not decided a presidential election since 1824, when it chose John Quincy Adams to be the sixth American president.

Mr. Bloomberg has denied that he plans to run.