Pelosi rallies U.S. House Democrats on possible presidential election decision

WASHINGTON, Sept 28 (Reuters) - U.S. House of Representatives Speaker Nancy Pelosi is rallying Democrats to prepare for a once-in-a-century election scenario requiring Congress to decide the outcome of the presidential race, if neither Democrat Joe Biden nor President Donald Trump wins outright.

In a campaign letter to colleagues, Pelosi told her fellow House Democrats that recent comments by Trump demonstrate that he could ask the House to decide the race if it is not clear which of the two had received the minimum 270 Electoral College votes in the Nov. 3 presidential election to gain office.

Trump repeatedly has questioned the security of mail-in ballots, which could take a while to tabulate given the high number of voters likely to opt for using them this year.

Democrats fear that the president could attempt to have the count of those votes cut short in an attempt to have the election outcome determined by the House.

Under the U.S. Constitution, the House would vote by state delegation to settle such a contest, with each state casting a single vote. While Democrats control the chamber by 232 seats to 198, Republicans control a majority of 26 state delegations, vs. 22 for Democrats. Pennsylvania's delegation is tied, while Michigan has a 7-6 split between Democrats and Republicans and an additional seat held by a Libertarian.

The House has not determined the outcome of a presidential election since 1876.

Pelosi called on Democrats for "an all out effort" to capture additional Republican-held House seats, which they might need if a decision on the presidential election spills over into next year. She also urged Democrats to marshal resources to support the House Majority PAC, a political action committee committed to promoting Democratic candidates for the House.

"Because we cannot leave anything to chance, House Majority PAC is doing everything it can to win more delegations for Democrats," Pelosi wrote.

House Republicans and their aides were not immediately available for comment. Like Democrats, they too have political operations aimed at expanding their numbers in the House. (Reporting by David Morgan and Susan Heavey; editing by Richard Cowan and Alistair Bell)