Rep. Brendan Boyle (D-PA) announced on Monday that a reliable, unidentified source told him that Vice President Joe Biden is running for president.

Boyle tweeted that he had a “very good source” that Biden will announce his candidacy.

Boyle also noted that former President Bill Clinton announced his candidacy late in October 1991 before winning the White House in 1992. Although Biden has been undecided, he’s emerged as an unofficial favorite in the Democratic presidential race.

If Biden announced, that would surely put a huge dent in Hillary Clinton’s supporter base. A definite announcement is expected to occur on Wednesday.

For more on this story, visit The Hill “Biden is running, says lawmaker”