New Hampshire Republican Sen. Judd Gregg, a key participant in Saturday's late-night bailout negotiations, said Sunday afternoon that both presidential candidates played a part in the deal that was reached and that final congressional votes are likely Monday.

Gregg, the ranking Republican on the Senate Budget Committee, also said negotiators Saturday night were told in no uncertain terms from leading economists that a meltdown on Wall Street was imminent if the Bush administration's $700 billion plan was not approved as soon as possible.

"Getting this done soon, promptly, is absolutely critical to the confidence of the markets," Gregg said. "I can't understate that issue."

Both Democratic presidential nominee Barack ObamaBarack Hussein Obama'Too Far Left' hashtag trends on Twitter Krystal Ball: Patrick's 2020 bid is particularly 'troublesome' for Warren Deval Patrick: Biden 'misses the moment' in 2020 campaign MORE and GOP nominee John McCainJohn Sidney McCainDonald Trump's 2020 election economic gamble 2020 Democrats make play for veterans' votes The Memo: Democrats confront prospect of long primary MORE were in close contact with the lead negotiators throughout the nine-hour session Saturday afternoon and evening, Gregg said, and he confirmed media reports that economists' perspectives were sought as well.

On other key points, Gregg said: