(CNN) Former Massachusetts Gov. Deval Patrick told friends and allies in phone calls on Wednesday that he has made a decision to run for president, two people familiar with the matter say.

Plans for the timing of his formal announcement were still in flux Wednesday, with attention on impeachment, but a source familiar with the plans tells CNN that Patrick will officially file for the New Hampshire primary on Thursday in Concord after he appears on "CBS This Morning."

The odds could be incredibly steep for a late entrant like Patrick, who is not well known nationally and does not have personal wealth to finance a campaign. Patrick has missed the deadline to appear on the primary ballot in Alabama and Arkansas. The deadline to file in New Hampshire is Friday.

Patrick could seize upon potential advantages in early-voting states: He is from Massachusetts, which is next door to New Hampshire, home of the first-in-the-nation primary. And being one of the country's first African American governors could be politically beneficial in South Carolina, where a majority of Democratic primary voters are black.

CNN reported on Monday that Patrick was seriously weighing whether he could make a credible last-minute entry into the Democratic Party's crowded primary contest after previously ruling out a bid late last year.

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