UPDATE 3-US Senate Democrats unveil new energy tax plan

(Adds analyst comment, updates record oil price)

By Chris Baltimore

WASHINGTON, May 7 (Reuters) - Democrats in the U.S. Senate on Wednesday unveiled a new energy package that would revoke $17 billion in tax breaks extended to big oil companies like Exxon Mobil Corp (XOM.N: Quote, Profile, Research) and slap a 25 percent windfall profits tax on firms that don't invest in new energy sources.

The day that U.S. oil prices hit an all-time peak of $123.93 a barrel, Democrats moved to act on soaring gasoline pump prices, which are a growing political liability in the November presidential election.

The Consumer-First Energy Act -- assembled by Senate Majority Leader Harry Reid and other key Democrats -- would tax big energy companies, halt filling the emergency U.S. oil stockpile, and seek to put checks on oil market speculation.

The Democrats' energy bill seeks to lay the blame for record-high gasoline prices over $3.60 a gallon on the Bush administration, big oil companies like Exxon and the OPEC oil cartel.

"The Bush administration has led us down the path of the most significant energy crisis we have had in decades, if not in all time," Reid told reporters.

Meanwhile, oil traders are "making out like bandits," oil companies are "making money hand over fist," and "oil-rich countries are thumbing their noses at American consumers," Reid said.

The American Petroleum Institute, which lobbies for big U.S. oil companies, said Democrats' plans would discourage investment in energy production and lead to less supply.