Polls consitently show voters are frustrated with both Republicans and Democrats, but experts say don't expect that frustration to fuel the launch of a third-party challenger for president in 2012.

The Miami Herald speaks with a number experts who say it's highly doubtful that we'll see another Ross Perot style candidacy.

"The cautionary tale for any third-party candidate," said Cary Covington, a political science professor at the University of Iowa, "is to remember that the last time a third-party candidate even finished second in a presidential race was 1912."

Since former President Theodore Roosevelt took second that year as a Progressive Party candidate, significant obstacles have largely shoved third-party candidates to the margins of elections. Simply put, Democrats and Republicans have an easier time raising money, getting listed on state ballots and winning enough states for shots at Electoral College majorities.

Political scientists they say those obstacles probably will prevent today's widespread voter disillusionment from translating into a credible electoral challenge.

"It's almost insurmountable," said Dr. Holly Brasher, a professor of government at the University of Alabama at Birmingham. "Until one of these left or right or center organizations has some continuity from year to year, I don't ever see it happening."